Building OldSchool's adherence calendar: turning dose taps into a day you can trust
A monthly adherence calendar looks like a single colored dot per day. Here's the event model, the day-status rules, and the on-time math behind it, on-device.
Building Subly: the calendar math behind subscription renewal dates
Predicting a subscription's next charge date sounds trivial until you hit month-end billing, leap years, and trial conversions. Here's how Subly gets it right, on-device.
Building Granyn: a budget tracker with no bank login, in three tables
How Granyn tracks spending across currencies and catches recurring bills without linking a single bank account — the Room schema and the trade-offs behind it.
Building Stocky: predicting what your kitchen runs out of — on the device
How Stocky turns a barcode scan and a bit of usage history into a shopping list that shows up before you run out — with all the math, and all the data, staying on your phone.
Local-first Android in 2026: SQLite, Room, and keeping user data on the device
A 2026 guide to building local-first Android apps with Room and SQLite — schema design, migrations, WAL, exports, and when (and when not) to add sync.