Best I’ve found. – Free Guitar and String Instruments Chromatic Tuner with Tone Generator - Apple Watch Edition Review

I’m looking for a way to read the pitch of stringed instruments for the purpose of tuning and repair. This app is the closest I’ve found, but unfortunately doesn’t pinpoint the value. It gets to within 15% and the reading makes quantum leaps as you tune up and down which are not tight enough for my purposes. For regular tuning (for players) it’s fine.
Review by MaxHollister on Free Guitar and String Instruments Chromatic Tuner with Tone Generator - Apple Watch Edition.