Independent iOS Studio
AppTheory
Small apps, built carefully. And notes from the build.
Read the Blog
Apps
FretNinja
Every way to play a chord
A guitar chord voicing explorer for iPhone. Type any chord and see every playable way to finger it across the neck.
View FretNinjaLatest Updates
All posts →Most Chord Apps Show You Shapes No Hand Can Play
Search the App Store for a guitar chord dictionary and you will find apps advertising thousands of voicings per chord. It sounds generous....
Building an iOS App with Claude in Xcode: An Honest Account
A note on what building an iOS app alongside an agentic coding assistant is actually like, minus the marketing.
Voice Leading Is a Shortest-Path Problem
Ask a guitarist to play Cmaj7 to Am7 to Dm7 to G7 and most will jump between memorised shapes, often travelling half the neck between...
About
AppTheory is a one-person iOS studio. The apps are small and focused, built to do one thing properly and then stay out of your way. The blog is the other half — the bugs, the fixes, and what building with AI tooling is actually like.
Contact
Questions, bugs, or feature requests: silo424@icloud.com — replies usually come within a few days.