When comparing Rainlendar vs Lightning Calendar, the Slant community recommends Lightning Calendar for most people. In the question“What are the best calendar apps for Mac OS X?” Lightning Calendar is ranked 12th while Rainlendar is ranked 14th. The most important reason people chose Lightning Calendar is:
Wherever Mozilla Thunderbird can be installed, the Lightning calendar can follow: Windows Linux MacOS
Ranked in these QuestionsQuestion Ranking
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.
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.
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)
Wherever Mozilla Thunderbird can be installed, the Lightning calendar can follow:
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.
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.
Con Can be unstable
The calendar crashes from time to time when entering new data.
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.
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.
Con Not for all the versions
You have to downgrade Thunderbird just because Lightning didn't upgrade to the last beta version.
Con Requires third-party gmail integration
And it's not supported in 60+. Use the old versions if you want anything to work.