Connect electronic drums to an iPhone: separate MIDI from audio
Timing practice needs two paths: the app receives stroke data, while you hear your kit and the exercise. MIDI carries the data. Audio carries the sound. A connection can support one path without providing the other.
USB-MIDI: check the data port
Look in your module manual for the port that supplies USB-MIDI to a computer or mobile device. A USB socket intended for storage is not automatically suitable. The module also needs a MIDI operating mode supported by the iPhone. USB-C describes the connector shape; it does not prove compatibility. Use a data cable and consider power requirements for an appropriate adapter or hub.
Lightning and five-pin MIDI
An iPhone with Lightning needs a suitable camera/USB adapter for a USB connection. Some combinations require additional power. A module with only five-pin MIDI DIN sockets needs an active, iOS-compatible MIDI interface. A passive DIN-to-USB cable does not replace an interface. The module, phone, adapter and cable combination still needs a device test.
Bluetooth-MIDI differs from Bluetooth audio
A Bluetooth-equipped module may receive music wirelessly without sending stroke data over Bluetooth-MIDI. Check the two functions separately. On the Roland TD-27, Bluetooth audio is not the MIDI path to the trainer; USB is relevant for MIDI. Other modules require their own documentation. Wireless audio output can introduce additional delay that becomes noticeable during practice.
Plan how you listen
A MIDI connection does not automatically bring your module’s sound into the iPhone. Depending on your equipment, you can use headphones on the module and feed accompaniment into its audio input. Other setups use an appropriate audio interface or mixer. Check levels and connections at a low listening volume. Establish the sound path, then configure and calibrate app input.
What applies to the MILLITACT beta?
The app is in a closed internal iOS TestFlight beta. Microphone mode detects stroke times without reliably distinguishing drums. This website illustrates possible connection paths; it does not promise verified compatibility with every device. Include your iPhone, module and proposed connection when asking about beta access so the combination can be tested specifically.
Manufacturer guidance: Apple · Roland TD-27
Explore the timing example