Support
Let every string ring true.
A little help for your next practice. These guides cover cTuner 1.0 for iPhone and iPad.
Talk to us.
Email cpoapps@gmail.com in English or Dutch. Include your device model, iOS version, app version, instrument, tuning and interface model if relevant. Please do not send an audio recording unless it is needed for your question.
Common questions
How do I get started?
Choose your instrument and preset in Tunings. Return to Tuner and tap Start listening. Allow microphone access. Pluck one open string gently, mute the other strings, and let the note settle. Left means the pitch is flat: tighten gradually. Right means sharp: loosen gradually. Green confirms the pitch is inside your chosen tolerance.
What is the difference between Auto, Manual and Chromatic?
Auto finds the nearest string within your preset, including its octave. If a string is far from the desired note, tap that string to lock Manual mode. Manual also lets you choose each paired string on a 12-string guitar or mandolin. Chromatic finds the nearest note among all twelve notes. You turn the tuning pegs; the app does not physically adjust the instrument.
Why is no note detected?
In iOS Settings → Privacy & Security → Microphone, allow cTuner. Reduce background music and noise. Play one string clearly and wait for a stable tone. For an interface, check the cable, chosen input and gain. Raise very low gain or reduce it if the input clips. Multi-channel interfaces currently use channel 1.
Can I use an external audio interface?
Connect a compatible wired or USB interface and tap Start listening. Open the input selector beside or below the listening button, or Settings → Audio input. Choose an available device. Compatibility depends on your interface, adapter, power and system audio routing. Bluetooth input follows system routing and may introduce latency.
Can I change the reference pitch or tolerance?
In Settings, adjust A4 between 430 and 450 Hz; 440 Hz is the usual starting point. Tolerance ranges from 1 to 10 cents and changes when the app marks a note In tune. It does not change the target frequency. The speaker button plays your selected reference note and pauses input while it plays.
How do I make or remove a custom tuning?
Tap + in Tunings. Enter a name, instrument and the note and octave for each string in physical order. You can use one to twelve strings, from B0 through E6. Hold a custom tuning in the collection and choose Delete tuning to remove it. Notes use international A–G names; B is H in German notation.
What about landscape, appearance and language?
Rotate your device to use the landscape workspace. The app follows its window size and preserves your selected string while resizing. Settings offers Light, Dark and Auto appearance. The app follows your preferred supported language: English, Dutch, German, French, Spanish, Italian, Brazilian Portuguese or Simplified Chinese. Change it in iOS Settings → Apps → cTuner → Language when available.
Why did listening pause?
Listening stops when audio is interrupted, the app is backgrounded, or the app becomes inactive outside a pending microphone permission request. Tap Start listening to resume. If you disconnect or reconnect an interface, check the selected input before playing again.
Is my audio recorded?
No. Live audio is held briefly in memory to estimate pitch and level, then discarded. cTuner never saves or uploads instrument audio. No account is needed. Read the privacy policy for details.