uhabits

Loop Habit Tracker (uhabits) is an open-source Android app for creating and maintaining long-term positive habits. It supports both simple yes/no habits and measurable ones, such as distance run or pages read, with flexible schedules like every day, a set number of times per week, or only on chosen days. Everything is stored on the device and the app runs entirely offline with no account required. A habit strength score, streak charts, calendar history and home-screen widgets show progress over time, and habit data can be exported or backed up to a file if you want to move it to another phone.