A free app for Android, by c-shock.

Being organized is one of the keys to productiveness. Through AA Calendar, you can now systemize your schedule, structure plans, and sync everything together with just a few taps on your device. Install now!

Once you install the AA Calendar, here are the following features that you can have access to:

Editing schedules, memos, anniversaries, goals, etc.
Sort by D-Day
Setting a Reminder
Setting schedules that are on repeat
Setting lists of priority
Checklist
Voice input
Widget for calendar
Customizable widget (modifiable theme and size)
Exporting and importing data on Google Drive
Setting of password
Holidays synched on your Google Calendar