Simple Tuner with No Ads Support

The tuner needs the microphone. If you did not allow it, the app shows “Open Settings”: tap it and turn on Microphone. Check that the microphone below the cents is on (grey, not red). Right after the app opens, a very soft note may take a second to appear while the tuner learns the room; an ordinary note shows at once.

Steady sounds such as an air conditioner are learned and set aside automatically, in the background, whenever you are not playing. There is nothing to set up. The tuner follows one instrument at a time: when several people play together in the same room, or a clearly pitched sound continues in the background, it cannot tell which one is you. Bring the iPhone close to your instrument.

While the microphone is on, the screen stays on, so it does not go dark in the middle of a phrase on a music stand. Switch the microphone off with the microphone below the cents, and your iPhone's Auto-Lock applies as usual.

No. The microphone is used only while the app is open on screen and the microphone button is on. It stops when you lock the screen, switch apps, take a call or use Siri. If it does not resume by itself, tap “Resume”. You can switch it off yourself at any time with the microphone button.

Most listeners begin to notice a difference between two notes at around 5 cents, so ±5 is shown as in tune. Up to ±15 cents is shown in white rather than red: beyond it, a note is out of tune to almost anyone, beating nearly four times a second against an in-tune A4. Players in ensembles also bend some notes on purpose, for example a major third about 14 cents lower than equal temperament, to make chords ring. The colour is a rough cue; the number of cents is exact, so read it when you practise for closer tuning.

The tuner measures your pitch about 25 times a second, and the lines glide between measurements without ever going past the measured pitch. While a note holds still, small flickers in the measurement are smoothed away; when your pitch moves, the lines follow at once. The number changes only when the pitch moves by three quarters of a cent or more, so it does not flicker between two values. With Reduce Motion on, the lines move straight to each new measurement instead of gliding.

Yes. The detected note and how many cents sharp or flat it is are read out, or that it is in tune. Concert pitch is a value you adjust by swiping up or down. The lines themselves are not read out.

No. Sound from the microphone is analyzed on your iPhone as it arrives, and is never recorded, stored or sent anywhere. The app collects no data and never goes online on its own. See the Privacy Policy.

With test signals, the measured pitch is within a few cents across the whole range. In real use the result also depends on the instrument, the room and the iPhone's microphone. It is a practice tool, not a certified measuring instrument.