Etar

Etar is an open-source calendar app for Android that follows Google's Material Design guidelines, making it feel right at home on any modern Android device. It is built on top of the Android Calendar Provider, meaning it syncs with your existing calendar accounts (like Google or Outlook) while keeping the app itself completely private and ad-free. It is a fantastic alternative for users who want the look and feel of a native Google app but with the transparency and security of an open-source project. It is simple, fast, and effective.