What can a player do if the Sqord app does not work on their mobile device?
Sqord, like virtually every other wearable that syncs to/connects with a mobile device uses a Bluetooth Low Energy (BLE) connection to do so. BLE is part of Bluetooth 4.0, which was introduced in 2010.
In order for the Sqord app to work on any device, that device must support Bluetooth 4.0.
If your device does not support Bluetooth 4.0, or does not work for another reason, you can always sync via a desktop or laptop computer with the help of a Sqord BLE dongle that you plug into any available USB port on your computer.