Hello. I want to hear if there is existing moon phrase app? When I going get my Fairphone 3 /e/ OS I hoping there existing such moon app, where it can tell when exactly it is full 
moon and giving forward messages of the events.
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I’m not sure about all the features but the Suntimes app might be what you’re looking for. Has alarms, too. Also a companion Suntimes Calendar add-on for your Calendar app.
Available via Apps or F-Droid.
Suntimes (Sunlight and moonlight times (and alarms)) - https://f-droid.org/app/com.forrestguice.suntimeswidget
There also are webcal and caldav calendars with the events that can be synced in your calendar app 
Okay thanks i going test it when i getting the OS on my Fairphone 3.
Ooh i didn’t knew that but that is cool!
Suntimes has a lot going on and is definitely for fans of solar and lunar activities. Overkill for me. I have a coworker who’s always asking about moonphases, moonrises, and moonsets. That’s why I installed it.
For those who just want basic info added to their calendar app, what Chimpthepimp mentioned is a good idea. On other ROMs I have ICSx5 installed, using a moonphases calendar from webcal.fi that syncs to the Calendar.