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For iOS, you will need the USB Camera Adaptor to connect your iOS device to your controller. Your device may still need to be powered with a 9VDC power supply. If your Apple device shows This accessory is not supported after you connect the controller, try using a better quality USB cable.
Please note that using a USB C to Lightning cable will not work. The Apple USB Camera Adaptor has a built-in circuitry to allow it to communicate to a USB device. More info here: https://discussions.apple.com/thread/251973717
For Android, you will need to use a USB B adaptor and suit whatever your Mobile device connection is (Micro USB, USB C etc).
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