ToDark is a simple, polished and elegant todo list/task management app with integrated calendar.
I’ve tested a ton of similar apps but fell in love with this one instantly.
The UI is very clean and the categories and progress circles are very well implemented.
Github page: https://github.com/DarkMooNight/ToDark
Play Store: https://play.google.com/store/apps/details?id=com.yoshi.todark
This is my go-to task manager as well.