When comparing Rainlendar vs Morgen.so, the Slant community recommends Morgen.so for most people. In the question“What are the best calendar apps for Mac OS X?” Morgen.so is ranked 5th while Rainlendar is ranked 11th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
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)
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.
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.
Pro Supports general CalDAV calendars
Pro Google synchronization
Connects to your Google accounts via OAuth.
Pro Easy to setup
Connecting to service accounts (such as Exchange) is easy and straightforward.
Pro Natural language
It supports interaction using natural language (English). For example "Schedule a meeting with John tomorrow at 11".
Pro One-click installation
First installation and updates are done with only 1 click.
Pro Supports Exchange calendars
Including Exchange, Outlook.com and Office 365 accounts.
Pro Free
Totally free and in active development.
Cons
Con Can be unstable
The calendar crashes from time to time when entering new data.
