How do I connect my keyboard to Simply Piano?

The best way is MIDI — either USB (a cable from your keyboard's USB-to-Host port to your device via the right adapter) or Bluetooth MIDI if your keyboard supports it. Then choose MIDI input in Simply Piano's settings. If you can't connect via MIDI, the app will listen through your device's microphone.

Does Simply Piano work without a cable?

Yes, two ways: Bluetooth MIDI (on keyboards that support it, like the Casio PX-S1100) or the device microphone (any keyboard). Bluetooth MIDI is accurate; the microphone is the less-reliable fallback.

My keyboard has Bluetooth — why won't Simply Piano see it?

Most likely your keyboard has Bluetooth *Audio*, not Bluetooth *MIDI*. Audio only streams sound to the speakers and can't send notes to the app. The Yamaha P-225 is a common example — connect it over USB instead.

Does Simply Piano work with an acoustic piano?

Yes, through the microphone — there's no MIDI to connect on an acoustic. It works, but expect the usual microphone-mode caveats around background noise and accuracy.