What are the best calendar apps for Linux?

Question

21

Options
Considered

1.4K

User
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43 mins

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Updated

Here’s the Deal

The Best 1 of 19 OptionsWhy?

Best calendar apps for Linux	Price	Platforms	Search
93 Calendar	-	-	-
85 OSMO	-	-	-
78 Evolution	-	Linux	Yes
72 Calcurse	Free	-	-
70 Orage	FREE	-	-

See Full List

18 Other Options Considered

Evolution

Top Pro

Sync multiple calendars at once

Evolution allows for multiple calendars to be synced and viewed, even multiple Google account calendars. All one needs is their log-in information and they will be set. See More

Top Con

Too complex

Although good and well integrated with GNOME, this application also offers email and contacts. If you are looking for an only Calendar application, this is too much for you. See More

ImpartialBelenus's Experience

Seamless integration with my mail server and also with Google calendar and contacts See More

Specs

Top Pro

Manages contacts, tasks, calendar and memos as well

Top Con

Poor integration in any non-GNOME desktop

It is written with GNOME in mind. See More

AdaptableShennong's Experience

It's like a virus. Close it and it'll reopen automatically until you remove the files even if you uninstall the package. No GMAIL calendar support. See More

Top Pro

Ability to change event status

Tentative, Confirmed and Cancelled See More

Top Con

Can be wobbly with EWS

Don't be surprised if you have to reboot it a couple of times during a working day, because error messages are piling up (e.g. connection lost, can't sync, can't store appointment, read only). Then again, is this Evolution, or what it connects to? And since such an occasional reboot is dwarfed by the fact that MS365 seems to make full IMAP/ SMTP access (close to) impossible (nice meeting invite, THX, but when is it?), just reboot and get some work done... See More

CleverAhPeku's Experience

Very easy to setup See More

Top Pro

Excellent GPG support

The integration with GPG is excellent. You can sign, encrypt, decrypt, authenticate and verify GPG signatures and GPG signed/encrypted email messages. All of that is just a setting away. See More

Top Con

RAM heavy

Very heavy on RAM usage. See More

SensibleIasion's Experience

The calendar is too basic for users who need it for heavy planning, color coding for events, is essential, which it does not have, just has some stupid icons that are not for purpose. Shame really because the email and address book is quite good See More

Top Pro

Works with vcal calendars, such as Nextcloud

Top Con

Tied to Gnome

Pulls in Gnome. See More

PowerfulChukwu's Experience

Improper support for webcal urls for icloud calendars See More

Top Pro

Supports exchange servers

Evolution is one of the few Linux desktop e-mail clients that's supports exchange servers. See More

Top Con

Only available on Linux

If you have to switch to another platform for whatever reason, you will need to search for a different email client. See More

Top Pro

Great integration with Gnome environment

Top Con

It's fat, bloated, and too dependent on fat, bloated Gnome

Installing pulls in too much Gnome dreck to be fast and efficient. Try Thunderbird instead there's less overhead. See More

Top Pro

Clean interface with 2 layout variants

Going to View > Preview has the option of switching between "Classical View" and "Vertical View". See More

Top Con

Calendar too basic

No color coding for events which is essential for daily use See More

Top Pro

HTML rendering is great

Of the many email clients available on GNU/Linux, Evolution has the best HTML renderer. It renders HTML and the entire email content exactly like it would appear on a full blown web browser. Not many email clients are capable of doing that. See More

Top Con

Broken CalDAV Support

Does not connect to Fastmail. See More

Top Pro

Good support for Google's services

Top Con

Can't choose different settings for each mail account

Settings have to applied to all mail accounts. See More

Top Con

Does not allow one to view notes attached to Google Calendar events

There is no way to see attached notes in a synced Google Calendar event, so if there is important information contained withing those notes using Evolution will mean the user will never see them. See More

Top Con

Broken Gmail support

See All

Calcurse

Top Con

Not made for app users

If you come to any professional or console software, expecting it to just behave like your Windows GUI apps, … you’re gonna have a bad time. You will need to know what you want, and actually tell the program so, by configuring it. So that then, it will fit you like a glove instead, of you having to fit into a dumbest common denominator mold. Like all professional software. See More

Top Pro

Supports arbitrary backends

E.g. CalDAV. Via its load/save hooks. See More

IndependentAglibol's Experience

Just what you expect from a normal text-UI (TUI) program. You configure it, and then it fits you like a glove. But you need to configure it. It’s no Windows program. And that’s a good thing. If you know how to use a computer, and not just colorful appliances that happen to run on a computer. It makes for quick work! Even fully automated work! See More

Top Con

No built-in help

The “help” function only tells you that you can use help on the program’s functions. But not what functions there are! How can you know what to ask for when you don’t know what there is? It’s like a text adventure game or Family Feud all over again. See More

Top Pro

Efficient

Uses very few resources, starts in the blink of an eye. See More

Martin Dalin's Experience

It uses keybindings that I already use for my terminal and I did not see another way to use this program. See More

Top Con

Keybindings also used by certain graphical terminals

The keybindings of either program have to be changed in that (rare) case. See More

Top Pro

Scriptable

You can use it in scripts via its command-line interface, and run scripts from it via hooks. So you can automate everything away, instead of being forced to use a GUI. A powerful feature. See More

PreciseAgrius's Experience

Cannot handle multiple caldav calendars at once. You currently have to add multiple config files and sync them one at a time. Also challenging to configure. Does not intelligently sort out acceptable media types for nextcloud on its own. See More

Top Pro

Fully customizable

Shortcuts, data sources, you name it. As real software should be. See More

Top Pro

Simplicity

See All

Orage

Top Pro

Integrates nicely into the taskbar

Top Con

Complicated setup

Some features are hard to set up. For example, setting up Monday as starting day for a week is not intuitive. See More

PerseveringAm-heh's Experience

Online integration is possible by setting up a foreign calendar with a caldav sync. See More

Top Pro

Set visual as well as audio alarms

Top Con

No online integration whatsoever

Friar Tux's Experience

I've tried some of the others in this list but Orage is the best so far. Sits on my desktop with highlighted event days and to do/events listed below calendar. Small but very useful. have used it for a couple of years. See More

Top Pro

Online integration is possible by setting up a foreign calendar with a caldav sync

AdaptableShennong's Experience

Very basic See More

Top Pro

Import calendar data via ICS export file

See All

Lightning Calendar

Top Pro

Free, open source

Lightning Calendar (just as Thunderbird) is completely free and open-source meaning that anyone can use it as well as look through the code or even use the code for their own projects. See More

Top Con

Available only as part of Thunderbird

No standalone version of the calendar app is available. And if you're just interested in Lightning Calendar and not Thunderbird, the app will have additional functionality and interface elements that will get in the way of using the calendar. See More

ReasonablePatollo's Experience

Generally good, but old events keep showing up even if deleted from the Google Calendar See More

Top Pro

Easily keep track of tasks

Bundled in with the calendar options is a tasks option that makes for an easy way to keep track of tasks in the same location as ones events. See More

Top Con

Does not always clear old events from the display, even when the event has been deleted

When accessing Google Calendar, every check shows that the event does not exist anymore. See More

DevotedTuriacus's Experience

Poor configurability. Wants to edit read-only entries merely by telling it to dismiss a notification See More

Top Pro

Cross-platform

Wherever Mozilla Thunderbird can be installed, the Lightning calendar can follow: Windows Linux MacOS See More

Top Con

No full CalDAV support

CalDAV support is more hackish than working reliably. E.g. certain fields are not supported, or alarms can lead to duplication of events or changes being reset. As CalDAV support is not truly built-in, and the extension does not have a high quality. See More

AdaptableShennong's Experience

Hit or miss if your version will support it. Broken third-party gmail integration. See More

Top Con

Requires third-party gmail integration

And it's not supported in 60+. Use the old versions if you want anything to work. See More

BrightPriapus's Experience

Can connect to almost any calendar server with readily available add-ons. See More

Top Con

Not for all the versions

You have to downgrade Thunderbird just because Lightning didn't upgrade to the last beta version. See More

TranquilOshunmare's Experience

continually trying to failing to sync, will fail until you cancel. See More

Top Con

Long term availability/ support

Although Thunderbird has an impressive track record and many years of reliable service, its continued existence has been doubtful more than once). For now, all seems good, but it would not be surprising if tomorrow it turns out Thunderbird "has left the building". See More

darlingchaos's Experience

Every time I've tried this calendar program it's broken in some fundamental way. Right now the vast majority of extensions won't work because of an update. It has always had the potential to be a really great email/calendar program, but Mozilla treats it like an unwanted guest. See More

Top Con

GUI makes you feel like it's 1995, and not in a nostalgic way

See All

KOrganizer

Top Pro

Multi-category

Top Con

Search events by text shows empty results for existing events

TalentedEpione's Experience

Has trouble with recurring events that have exceptions to them. If recurring even has an exception to the pattern at some point KOrganizer seems to not display any of the recurring events. Thus making it useless for complex calendars. I did verify that the akonadi back end did have the full set of events, KOrganizer just does not interpret them correctly. See More

Top Pro

Long-time support

Top Con

Has issues with recurring events with exceptions

Has trouble with recurring events that have exceptions to them. If recurring even has an exception to the pattern at some point KOrganizer seems to not display any of the recurring events. Thus making it useless for complex calendars. After verifying that the akonadi back end did have the full set of events, KOrganizer just does not interpret them correctly. See More

Top Pro

Integrated into KDE

It can be used by clicking on the datetime in the bottom right corner. See More

Top Con

Does not connect to secure CalDAV server

Top Pro

Imports well from Google Calendar

Top Con

Does not connect to Fastmail

Top Pro

Easy and intuitive to use

Top Con

Crashes even whilst trying to launch the app

Top Con

Crashes when trying to add new event

Top Con

Requires KDE

See All

Google Calendar

Top Con

Privacy concerns

Google integrate all their services to connect and mine information on an individual to better profile and target advertising. See More

Top Pro

Integrates well with other Google services

Google Calendar is part of the Google ecosystem, it integrates with services like Google Now, Google Maps and Gmail. See More

igeek's Experience

This was exactly I've been looking for. It's a tool written by people who actually use it. This calendar makes scheduling tasks very straightforward, you'll wonder what you did without it. See More

Top Con

Web app

No native application with native notifications and such available. See More

Top Pro

Allows setting e-mail reminder notifications

Google calendar allows setting how many reminders are needed with each having the ability to set how long before the event the notification should remind. See More

AdaptableShennong's Experience

Everything online, requires browser opened all the time. See More

Top Con

Proprietary web app

Being that this is a Google app it is proprietary which means Google holds full control of the app. Though there are APIs there is no official app on offer other than a Chrome Webstore app and the webpage. This can limit how one uses the official interface of the app. See More

Top Pro

Integrates with Google Maps for directions

The app leverages Google Maps when adding location for an event by offering suggestions as well as offers opening Maps to help get directions to an event. See More

DevotedTuriacus's Experience

Don't want to have to run Chrome just to have a calendar (for that matter, don't want to run Chrome at all) See More

Top Con

Google knows your schedule

Top Pro

Color-coding for events and calendars

The app will color-code different calendars in different colors as well as allow selecting a different color for each event. See More

NobleGuanyin's Experience

Takes too long to sync with ical and no ability to manually force a sync making it essentially useless across platforms. See More

Top Con

Not minimalist

There's a lot of unnecessary complexities. See More

Top Pro

Supports non-Google calendars

Google Calendar can be integrated with any calendar that supports iCalendar format, including Exchange and iCloud, via URL, but it has to be done using the web client. See More

PersistentEulabeia's Experience

Isn't reliable. You change events and they may not register properly making your schedule a mess. See More

Top Con

It is not reliable

Sometimes it silently doesn't register a change in an event, making you look dumb when you miss an appointment. See More

Top Pro

Free and ad-less

There are zero advertisements in the web app and it is offered for free. This is done in order to get users to their services where they will then learn about a person to use targeted advertising in other areas. See More

John J. Martinez's Experience

Es bueno, tiene todo lo que necesito, sin embargo, queda corto cuando no hay Internet, incluso podría decir que está fuera de concurso porque no es una aplicación offline totalmente, sin embargo, es la que más uso. See More

Top Con

Once you create a event on a Calendar, you can't move to a different Calendar

Top Pro

Allows subscribing to public calendars

Through the Google Calendar's web client, it is possible to subscribe to any public calendar. Google also maintains a list of public calendars for various sports events and holidays in different countries and for different religions. See More

TallLakapati's Experience

Bloated app that is running browser in the background. Especially since it prefers to work with that abomination Google Chrome,. See More

Top Con

Almost no configurability

Configurability is very minimal. If you need anything proper, you’re out of luck. (Assume Apple levels of choice.) … So it’s not suitable for professional work. (Esp. in the EU, where it’s straight-up illegal due to GDPR.) See More

Top Pro

Events can be added using natural language

The application allows natural language input for events. For example, typing in "Lunch with Stuart Kearney at 2pm" will set the appointment. See More

Yanis's Experience

Google again does the work well ! See More

Top Con

Not free

You just pay with your data. Everything you enter, will be used against you. (E.g. in advertisement on any site using google for advertisement.) See More

Top Pro

Offers creating events from e-mail messages based on content

Google Calendar integrates with e-mail for quickly creating events from e-mails that contain the word "meeting" or dates or times, or any other information about events or plans that it can understand. See More

FlexibleMictecacihuatl's Experience

privacy is an issue See More

Top Con

Cumbersome and slow to get things done

Everything takes more work than it should, because you have to avoid and undo all the “smart” “automagic” stuff that is only useful for the smallest common denominator of users. See More

Top Pro

Calendar widget

Simple and easy to use widget once the app is installed. See More

Ajay Kumar Rawani's Experience

Awesome ! See More

Top Con

Strenuous event creation procedure

Instead of just being able to drag, the user has to submit a lot of info such as start time, location, etc. See More

Top Pro

Advanced functionality available through IFTTT

With IFTTT support users can extend the functionality of Google Calendar with things such as Evernote integration or weather notification support. See More

Top Con

Cannot see Exchange calendar

Top Pro

Comes pre-installed on most Android devices

Google Calendar is a free Android calendar app without ads that comes already installed on Android devices that have stock support for Google Services. See More

Top Con

Setting up CalDAV or iCAL from other sources is not working or not working well

A lot of people share events between different sources: professional, private, family or friends. Not everybody is on Google and of course a lot of corporations. See More

Top Pro

Can set on-screen and e-mail reminder notifications

Google calendar allows setting how many reminders are needed with each having the ability to set how long before the event the notification should remind and if it should be done via on-screen or e-mail notification. See More

Top Con

Unable to make notes about appointments

You used to be able to make notes about appointments and location, but the current version does not allow you to do any of that. Also, it is almost impossible to tailor the calendar app to eliminate things like others posting to your calendar or types of holidays in which you are not interested. See More

Top Pro

Clean design with 5 different views including an excellent schedule view

Google Calendar has a monochrome base design that's accented with colored-coded events and image banners that separate months in schedule view. The app has 5 different views - schedule, day, 3-day, week and month. Day, 3-day and week views split up the days horizontally and hours vertically. Month view lays out all days in a grid and displays up to 3 events in a day. Schedule view displays an agenda view that allows browsing all events by swiping vertically. Additionally, the way events are displayed in the agenda view is context-aware. For example, adding an event called "gym" will display the event on a background with a dumbbell. All views except for month view can be split horizontally to display a condensed month view at the top that can be navigated by swiping horizontally. Events can be added from any view by clicking the red plus button that's available at the bottom-right corner of the screen. See More

Top Con

Setting up non-Google calendars requires accessing web client

There is no ability in the Android app to access other calendars. This limits the usefulness for people that use more than one calendar, such as OSX and iOS users. See More

Top Pro

Straightforward event creation with autocomplete

All views have an option of adding a new event by tapping the plus sign at the lower right corner of the screen. This opens up a form and allows the user to add a location, start/end times, guests, description, color-code as well as choosing if it's an all day event, how often it repeats, how many and what kind of reminders are needed and setting the users availability and privacy settings. See More

Top Con

Time zone is incorrect no matter what's done

For example, timezone for Moscow is 1 hour off. This makes the calendar unusable in Russia. See More

Top Pro

Awesome flairs / images view inside the agenda view / event page

Whenever you enter agenda / event title with the keywords (when available), the event will show up interesting flairs whenever the keyword inside the agenda / title you typed matches the flairs that are available inside the system, examples such as haircut, cycling, swimming, coffee, movie etc. See More

Top Con

Weak default view

Even if month is set as default view, as soon as you touch a day or an event, you have to carefully select twice to get back to month view. See More

Top Pro

Lots of third-party widgets

Google Calendar comes with a home screen widget, and there are also many third party widgets developed for this calendar app. See More

Top Con

No natural language input support

The Android app has no natural language input support, while it's available using the web client and in a limited capacity using Google Now. See More

Top Con

Slow syncing of external calendars

Google Calendar is known to sync external calendars very slowly, takes hours if not a full day before the updated events are reflected. See More

Top Con

No vertical scroll

Like iOS and outlook for Android. See More

Top Con

Some recurrence options not available

If you want to add a recurring event based on quirky (but normal) calendar rules, it's not supported by Google Calendar. For example, if you set up a financial calendar in Google Calendar and an event falls on a weekend or bank holiday, Google Calendar cannot schedule the occurrence properly. Worse yet, if you submit those calendar occurences via VEVENT details, Google Calendar displays different information if you use the mobile calendar vs. the desktop web calendar. See More

Top Con

Does not work well with Apple / iCloud calendar

Apple and Google calendars have syncing issues, which is annoying if you want to have shared calendars with friends / family. See More

Top Con

Month view shows limited information about the event

Month view does not show how many events there are in each given day or color-code them in any way, only informs of their existence. See More

Top Con

No weather forecast

The Android app version of Google Calendar does not show any weather forcast information, even if it is added as an extra calendar in the web application. Being that weather is tied into Google Now, the absence is surprising. See More

Top Con

Google tasks do not show on Google Calendar

You can create tasks in your desktop Google Calendar but they will not sync nor show up in your android Google Calendar. See More

See All

California

Top Pro

Integrates with the desktop in order to provide notifications

California offers desktop notification on most major DEs in Linux, which is great to know when events are happening while not having to have the app open in the foreground. See More

Top Con

Currently not in active development

Yorba, the group that developed California, is no longer actively developing software. While Geary (Yorba's mail client) has been adopted by the elementary teams as "Pantheon Mail", both elementary and Gnome have their own calendar projects and it is unlikely that either of them will contribute to California in the future. That being said, California uses evolution data server for all backend/sync/storage related tasks, which should hopefully make it possible to use it even if 3rd party vendors change their APIs/protocols etc. As long as EDS does not introduce backward incompatible changes or any major California bugs occur (it has been working fine for me so far), the current state of California should remain usable for quite a while. See More

DevotedTuriacus's Experience

Looks like it could be a useful application, if it wasn't abandonware. See More

Top Pro

Events can be added using natural language

The application allows natural language input for events. For example, typing in "Lunch with Stuart Kearney at 2 pm" will set the appointment. See More

Top Con

Currently no drag and drop support

There is no way to drag events in the app for easy switching, it all has to be done manually which can be a lot of work to move many things around. See More

MerryNibhaz's Experience

I couldn't install it because as others mentioned, it is no longer in development. See More

See All

Rainlendar

Top Pro

Blends in with the desktop

This calendar stays out of your way while remaining readily available to tell you what's coming up. The Shadow skin make it look like a wallpaper calendar but has the benefit of being interactive. See More

Top Con

Can be unstable

The calendar crashes from time to time when entering new data. See More

ImmaculateKresnik's Experience

Rainlender 2 sits on my desktop and lets me sync with my Caldav server. It runs on Linux and Windows so my calendar and tasks are up to date on my personal machine as well as my work machine. See More

Specs

Platforms:Windows, Linux, Mac

Top Pro

Integration

Your calendar data doesn't need to be stored with your computer. Data can be retrieved from Google, RTM, and even Outlook. (With the pro version removing annoying unregistered marks) See More

Top Con

Local calendar looses sync sometimes

CreativeUttu's Experience

After using the Pro Version for a while, I deinstalled it. Too often it would not properly sync and I would have to manually reset the local data to fix it. I don't know if I ever actually missed something because of that, but it leaves a bad feeling. See More

Top Pro

Customizable

Take control of your calendar by scripting new functionality, take skins already created, or just disable all the fluff. Rainlendar provides a platform to present your data in the way you desire. See More

InventiveMokhNaana's Experience

I have used for years. Can put multiple calendars on desktop. Invisible background lets desktop be seen. Has todo and event lists. See More

Top Pro

Works on Linux and Windows

ReverentXipeTotec's Experience

Excellent app for Linux (have yet to try Windows version). Syncs seamlessly with Google calendar & Tasks. Not many such apps include tasks synchronization. See More

InsightfulMeretseger's Experience

Network calendars (caldav or Google Calendar) only in payed pro version. See More

See All

gsimplecal

Top Pro

Very simple

gcalcli

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khal

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Maya

Top Pro

Gnome style calendar with handy event panel

Top Con

Event panel needs bug fixes - often displays events out by a day, if at all

ical

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score 353 · Accepted Answer

Calendar

Top Pro

GNOME native integration

Top Con

Extremely buggy

EmpatheticFebris's Experience

Simple but buggy See More

Top Pro

Synchronisation

It has online accounts integration. See More

Top Con

Poor interoperability with online calendars

Does not connect to Fastmail. See More

TallLakapati's Experience

Calendar sees my company calendar account TWICE and therefore shows EVERY event twice. Cannot disable one of them, as it sees them as the same item. You uncheck one, and it disables BOTH. Has NO way of configuring it (it's a GNOME project, usability is not of any concern to the developers, as usual) See More

Top Pro

Currently in active development

GNOME Calendar is improved with every release cycle of GNOME. See More

Top Con

Cannot print

JoyousJuthrbog's Experience

Added web calendars keep vanishing on app startup. See More

Top Pro

Simplicity

Calendar for GNOME aims to find the perfect balance between features and usability. See More

Top Con

Far too simple

SensibleMafdet's Experience

terrible at syncing to online account, very buggy See More

Top Con

FAR too tied into the GNOME infrastructure

The UI and configuration presume you are running GNOME, and has the ugliness of a GNOME application. Configuration, as is usual for any GNOME application, is pretty much nonesistent. See More

CredibleRhadamanthus's Experience

Keeps bugging See More

Top Con

Can't read 'all-day' events with dark theme

Text is white on light blue with dark themes. The workaround: assign all-day events to just one hour. See More

ConfidentTiw's Experience

Can't print, that is, the program does not support printing and system printing (Ctrl-P) does nothing. See More

Top Con

Can't import ics files

CaringLahamu's Experience

good See More

Top Con

Continues to pop-up reminders that are turned off and they cannot ever be removed

The GNOME Calendar displays pop-ups from an old Google Calendar that was used. That Google Calendar has long since been removed from GNOME, and even with the notifications turned off on the GNOME Calendar, the pop-ups still happen. See More

PracticalHelernus's Experience

Does not synchronize reliably with Nextcloud See More

Top Con

Incorrect appointment times when importing .ics calendars

TrustworthyEmesh's Experience

Syncs with old Google calendars that were deleted years ago. Continues to popup reminders that are turned off. Apparently, once something's added to the calendar it cannot ever be removed. See More

Top Con

No support yet for WebCal

No support yet for WebCal, such as those offered by Facebook events. A workaround exists. Since this application uses the same background services as Evolution, installing it and adding the WebCal calendars there, also adds them to GNOME Calendar. See More

Top Con

Only works on GNOME

See All

The Best 1 of 19 OptionsWhy?

My Recommendation for Calendar

My Recommendation for Calendar

GNOME native integration

Extremely buggy

Synchronisation

Poor interoperability with online calendars

Currently in active development

Cannot print

Simplicity

Far too simple

FAR too tied into the GNOME infrastructure

Can't read 'all-day' events with dark theme

Can't import ics files

Continues to pop-up reminders that are turned off and they cannot ever be removed

Incorrect appointment times when importing .ics calendars

No support yet for WebCal

Only works on GNOME

18 Other Options Considered

My Recommendation for OSMO

My Recommendation for OSMO

Local only

Nice GUI

Crashes suddenly due to segmentation fault

My Recommendation for Evolution

My Recommendation for Evolution

Sync multiple calendars at once

Too complex

Manages contacts, tasks, calendar and memos as well

Poor integration in any non-GNOME desktop

Ability to change event status

Can be wobbly with EWS

Excellent GPG support

RAM heavy

Works with vcal calendars, such as Nextcloud

Tied to Gnome

Supports exchange servers

Only available on Linux

Great integration with Gnome environment

It's fat, bloated, and too dependent on fat, bloated Gnome

Clean interface with 2 layout variants

Calendar too basic

HTML rendering is great

Broken CalDAV Support

Good support for Google's services

Can't choose different settings for each mail account

Does not allow one to view notes attached to Google Calendar events

Broken Gmail support

My Recommendation for Calcurse

My Recommendation for Calcurse

Not made for app users

Supports arbitrary backends

No built-in help

Efficient

Keybindings also used by certain graphical terminals

Scriptable

Fully customizable

Simplicity

My Recommendation for Orage

My Recommendation for Orage

Integrates nicely into the taskbar

Complicated setup

Set visual as well as audio alarms

No online integration whatsoever

Online integration is possible by setting up a foreign calendar with a caldav sync

Import calendar data via ICS export file

My Recommendation for Lightning Calendar

My Recommendation for Lightning Calendar

Free, open source

Available only as part of Thunderbird

Easily keep track of tasks

Does not always clear old events from the display, even when the event has been deleted

Cross-platform

No full CalDAV support

Requires third-party gmail integration

Not for all the versions

Long term availability/ support

GUI makes you feel like it's 1995, and not in a nostalgic way

My Recommendation for KOrganizer

My Recommendation for KOrganizer