To connect the GPW1 to your phone, you need to enable Bluetooth on the GPW1 first. Go to your phone's Bluetooth Settings page, search for Bluetooth devices around you, find GPW1 and tap Connect. You may need to enter a matching code.
Once the connection is successful, you can open the application you want to control on your phone and start using GPW1. Note that GPW1 can be connected to only one device. If you want to connect to other devices, disconnect the current connection first.