Something not working?

Work through these in order.

1. Wired: connect the controller before opening PadCoach, and make sure the cable is a data cable rather than a charge-only one. Many controllers also need external power through a powered hub, because an iPhone alone may not supply enough.
2. Bluetooth: open the app and use the pairing screen inside it. That screen is Apple's own Bluetooth MIDI pairing sheet, and it is the only way iOS will connect a Bluetooth MIDI device. Pairing in the iOS Settings app will not work: Bluetooth MIDI devices do not appear there.
3. Settings, Manage controllers: check inside PadCoach to see what the app can currently see.
4. Some controllers are not plain MIDI. Devices that speak a proprietary protocol, NI Maschine being the usual example, do not present themselves as a MIDI device to iOS, so nothing can see them. A class-compliant pad controller, an MPC style grid for instance, works.

You never need a controller to use PadCoach. The on-screen 4 by 4 pads are graded exactly the same way on timing. Only the Drumming With Dynamics course needs one, because a glass screen cannot tell a hard hit from a soft one.

The usual cause is that your audio went to the controller. A pad controller connected over USB often introduces itself to iOS as an audio device as well as a MIDI device, and iOS will happily route all sound to it. If that controller has no speakers, everything goes quiet.

PadCoach detects this and shows a banner naming the device it thinks your audio went to. To fix it, open Control Center, press and hold the audio card, and switch the output back to iPhone. You can also unplug the controller, check that sound returns, and plug it back in.

The other things worth checking: the silent switch, the volume while the app is in the foreground, and whether the metronome or backing volume has been turned down. Both live in the metronome panel in the lesson HUD.

Two settings exist for exactly this.

Latency calibration (Settings, Playing) nudges the whole timing judgment from minus 50 to plus 200 milliseconds. If your hits consistently read late, add a little. Bluetooth controllers usually need more than wired ones. There is a reset to zero next to it.

Slow practice is the other half. Tap the BPM readout in a lesson and drag the tempo down, as far as 30 BPM. The take restarts at the new tempo. Getting the shape right slowly and then walking it up is how the whole curriculum is designed to be played.

For reference: a Perfect is within 25 milliseconds either side of the beat, and the wider Good window scales with the tempo of the lesson.

The first five lessons are free and always will be. They are the whole of the first half of the First Beats course, and they finish on a complete boom bap groove played with both hands, so you get to a real result before you decide anything.

Everything after that is unlocked by a single one-time purchase. There is no subscription, no consumable, and no timer. Jam Mode and the reference book are not behind the paywall.

Open Settings, Purchases, Restore Purchases inside the app. The same button also appears on the unlock screen itself. Make sure the device is signed in to the same Apple Account that made the original purchase, because that account is what holds the entitlement.

If the restore does not find it, email me from the address on the receipt and I will help you sort it out with Apple.

Set it and every pattern mirrors for you: the finger prescriptions follow your leading hand, and the pad grid geometry stays where it is so what you learn still transfers to hardware.

You are asked during the first run, and you can change it any time in Settings, Playing, Handedness.

Your practice history is stored on the device itself and is not synced to iCloud, so it does not follow you to a new phone and it is removed if you delete the app. Your purchase does follow you, because Apple holds that against your Apple Account: reinstall and use Restore Purchases.