Trac was a general-purpose tracker — you define what you want to count (a habit, a mood, any metric), and the app logs entries, shows charts, and backs everything up to Google Drive. Built in Flutter, with SQLite for local storage and Firebase for app infrastructure like crash reporting and in-app purchases. It went through both the App Store and Play Store review processes and had real users. It's since been retired. The tracking-app space has plenty of well-maintained alternatives now, and it wasn't worth the ongoing maintenance for a side project. The app and its data model still work; it's just no longer actively developed.