When comparing Google Keep vs Simplenote, the Slant community recommends Google Keep for most people. In the question“What are the best cross-platform task apps?” Google Keep is ranked 16th while Simplenote is ranked 39th. The most important reason people chose Google Keep is:
1-step to take a note on Android: tap 'take a note'. Web version: cursor is on the note itself.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Easy to use
1-step to take a note on Android: tap 'take a note'.
Web version: cursor is on the note itself.
Pro Super fast to use
The focus on a minimal interface makes everything fast to use on both web and mobile. This comes in handy for when a note needs to be jotted down quickly, as there is little to no load times or faffing about trying to get to a space where the note can finally be recorded.
Pro Unlimited and seamless sync across all Google connected devices, from mobile to desktop
When a mobile device isn't in use, Google Keep can be accessed as a Chrome app or as a website. Basically, no matter the device being used or the OS on it, there is always a way to access the app. There is also no limitation to how many devices this can be done with, freeing up the user to always have access.
Pro Automatic saving
Automatically saves new changes so that nothing is lost.
Pro Useful Android home screen widget
The Keep widget lets users quickly see existing notes and add new ones.
Pro Notes can be grouped via labels
In addition to the ability to color-code notes, they can be labeled and navigated and grouped that way. This allows for easy organization, to then be found easily at a later date.
Pro Notes can be color-coded
Pro Cross platform
This app can be used seamlessly across all platforms including Android, iOS, and desktop computer platforms.
Pro Works as a great bookmarking tool as links added can optionally include a preview image
Keep has a great feature that allows you to save sites you visit as a special note type with a link and a preview image.
Pro Can share and collaboratively edit any item including lists
Keep allows sharing any item with other contacts and editing them together at the same time. This way a team can work together in real time, no matter their location.
Pro Really well implemented speech-to-text
Google has a lot of experience with speech-to-text functionality and they did a fantastic job with Keep. This means you can easily record spoken notes that can then be changed to a text based note.
Pro Notes can include photo and audio attachments
Notes can include multimedia attachments in addition to text.
Pro Supports drawing or writing notes by hand
Newer version of Google Keep now supports drawing on either a blank page, existing notes or in an image attached to the note.
Pro Both location- and time-based reminders
You can set reminders that bring certain notes to your attention when you arrive at a specified location or when it’s a specified time or date. Unfortunately you can only do one or the other for each note.
Pro Includes character recognition for text in images
Google Keep lets users take pictures of physical notes and makes the contents searchable within the app. This can be a convenient time saver for those that do not want to type out the necessary info, but rather take a quick snapshot of it.
Pro Drag and drop sorting
You can move cards manually, which is great for prioritizing to-dos. Within a card, you can also drag and drop items.
Pro Archives finished tasks
Any finished task is archived and can be searched at a later date.
Pro Very simple and clean interface
Simplenote takes a minimalist approach to its interface. There are no toolbars full of formatting options or extra features like notebooks to group notes. The entire desktop interface consists solely of a sidebar with your tags and trash filters, the list of existing notes with search, a button to add a new note and a simple view for looking an existing note or writing a new one.
Pro Geared towards fast usage
Unlike alternatives (such as Evernote) that are laden with features, Simplenote is fast to use and sync. Reviews from the Verge, Lifehacker, and a variety of other sources all describe using the Simplenote apps as very fast. While it may not be as feature-rich as other apps, the responsiveness of the app and simple interface keep it easy to use while never slowing down the user when they need to quickly take a note.
Pro Works offline
Users can edit and create documents offline, can then sync their content the next time they are online. This way a user can work even when there's no data connection without the worry of losing work.
Pro Desktop app is open source
The desktop version of Simplenote is hosted on the GitHub and since it is open source, it can allow developers to fork the code in order to improve the app.
Pro Can export your data
The program enables exporting of notes as text documents.
Pro Collaborative features
Notes can be shared with others or worked on collaboratively.
Pro Open Source
All of the Simplenote apps are open source and ready for your contributions! You can find the source on GitHub:
iOS: https://github.com/automattic/simplenote-ios
Android: https://github.com/automattic/simplenote-android
macOS: https://github.com/automattic/simplenote-macos
Electron (Windows and Linux): https://github.com/automattic/simplenote-electron
Pro "Time machine" style revision control on the notes
Each edit of a note is saved in order to allow the user to go back to a previous version of a document. This way, if mistakes are made or something is deleted, you can go back to the previous version without any hassle.
Pro Wide range of great clients with great sync
Official native apps are available on popular platforms such as Android, iPhone, iPad, Kindle, OS X, Windows and Linux. Open-source clients extend this support even more widely to various other platforms, such as webOS and the BlackBerry PlayBook. These apps embody the core philosophy of Simplenote: minimalism and focus on the note taking.
There are multiple unofficial clients (including the excellent Notational Velocity and NValt, a fork of the app with markdown support and other goodies.)
Pro Markdown support via web interface
There is support for Markdown when using the web app. This can be convenient for those who want to use Markdown in a particular note.
Pro Linux client available
Pro Excellent iOS app
Pro Excellent desktop client in the form of nvAlt
Cons
Con Google can access and mine your data
You have to be okay with Google analyzing and using your data in order to use Keep.
Con Messy if you have lots of notes
It can be difficult to organize notes because you can only create labels and not, for example, separate projects.
Con Organization is limited to just multiple tags for notes
There are no folders in Keep that you can move notes into. It makes the user interface more cluttered, and navigation gets more difficult.
Con Can be taken down some day
As Google is notorious for taking down services, you may end up with just a backup of your notes in XML format and a need to look for a substitute.
Con No ability to undo changes
There is no way to revert changes or restore text you may have accidentally deleted (however, you can restore entire notes for up to 7 days after deletion).
Con Synchronization bugs
There are some issues with synchronizing data including laggyness and returning old/deleted items.

Con No text formatting
No basic formatting like bold, italics. Makes it harder to do things like meeting notes. Keep is intended as a minimal and quick note taking app, but sadly for those that are looking for something more robust, the features are just not there.
Con Scrolling through notes is horrible
There are no options to decrease the surface area of the notes to make it easier to get an overview. Compare this to something like the Apple Notes or Evernote UI, for example. You can't organize nor have a glance of what you have.

Con Not free/libre
This application is proprietary, and thus cannot be modified or freely distributed.
Con Can be difficult to discover the features
Google Keep has slowly been introducing new features, but doesn't do a good job of helping you discover them.
Con Google account required
You're required to have a Google account in order to use the app.
Con Does not offer themes
There is no option for changing the color theme (such as a dark theme) unless you use a 3rd party extension.
Con Does not integrate with Google Calendar or Tasks
It does not integrate with Google Calendar or other Google Apps with the exception of "Google Now." Keep reminders can appear on Google Calendar, but you can not get reminders and use Tasks at the same time.

Con Too simplistic of an approach
Con No integrated social media sharing
There is no integrated social media sharing if you directly want to post your note to Twitter, Facebook, etc.
Con Not good at all for longer notes
With almost no formatting options whatsoever it's hard to actually use Keep for long-form notes.
Con Sharing within team doesn't work that well
You can share separate notes but not Projects, Wordspace, or Teams.
Con Not distributed
Cannot run on own servers as Keep will only run on Google's own servers. This increases the risks which are normally associated with handing over critical applications to a large (US) corporation.
Con No notifications when tasks are added to shared lists
Although the ability to collaborate on lists is advanced, Keep will not let you know when another person adds an item to a list you share.
Con No API
Con There is a label limit up to 50
Con No dedicated app for windows, linux, mac (except unofficial)
Con Cannot share groups of notes (e.g., labels)
Google's equivalent of groups are labels, which can't be shared. By comparison, Trello allows you to share boards with others. Trello also supports grouping through teams. Google Keep has no such concept.
Con Slow to save the updates
Saving is delayed by a moment and the saving status UI is unclear. You can lose updates if you close the tab too quickly.
Con Delay between to-do entries
The keyboard closes and reloads between to-do list entries, so the first letters or words may be missed if you’re trying to quickly create a list.
Con Notes get lost/deleted and can NOT be recovered
Since nothing is stored locally on the phone, everything can go missing. Google can't recover any of it.
Con No BlackBerry 10 app
No BlackBerry support apart from web.
Con No Windows Mobile app
No Windows Mobile app, and it is unlikely to ever be produced.
Con No note encryption at rest
Notes are encrypted in transit, but remain unencrypted on Simplenote's servers.
Con Limited ways to reorder notes
You are able to sort your notes alphabetically, date modified, or by last created. There is no way to drag and drop the notes to create a custom order.
Con No reminders
You cannot set reminders to revisit a specific note or complete a task.
Con No support for file attachments
Simplenote doesn't provide support for embedded attachments. This can limit the use for some as many other note-taking apps do support this type of feature.
Con Search is limited to one tag
There seems to be no way to find notes that have both tag X and tag Y. This isn't a big deal until you have a large library of notes, and want to cross-search for two things at the same time to vastly narrow down your search.
Con No way to import notes from anywhere
Con Web access only for updated browsers
They recently removed support for older browsers, and it's not working on the latest version of Waterfox. You need an updated version of a well-known browser.
Con No 32-bit version
Con The search function doesn't see tags
If you search for 'foo' you won't find notes with tag foo. In that regard, tags are completely isolated from the search.
Con No way to bulk-apply a tag
This is a typical workflow action in other apps: Do a search, multi-select notes among the matches, then apply or de-apply one or more tags to all these notes at once.
There's no way to do this in Simplenote. The only bulk operations are Delete and Pin-to-top.
Con No notification when changes made on a shared note
Currently, there is no way to be alerted when a change is made by another contributor on a shared note.
Con Save-to-disk feature is poor
The only way to download your data off Simplenote is via a "download zip" feature that unfortunately loses all the semantic structure of your data (tags, for instance).
Con No integrated social media sharing
The only way you can share notes with others is with a link you're given when you publish your note. There is no integrated social media sharing if you directly want to post your note to Twitter, Facebook, etc.
Con Lack of color impacts usability
There are two themes available, the default theme and a dark theme.
Both use only the single solid color (either white or black) for the background, so there is a lack of visual cues to separate what you're looking at.
