Prior to connecting any power meter to the app, you will need to ensure that you have correctly configured that power meter using its own software and that the firmware is up to date. Single-sided power meters may need to be configured so that they double the power from one side rather than try to pair with a second pedal, and dual-sided power meters may need to be configured so that they are paired and report combined power as a single device if possible. The ability to connect the power meters as two separate devices is possible on iPhone and iPad if this is required to get proper readings from your device.
How to connect
Single-sided power meters and Dual-Sided power meters that are set up to report unified power will show up in the Add Devices box with only one possible connection. Click on Connect to add it to the device connections screen.
If Dual-sided power meters are set up for dual or individual reporting, or if they can't be configured to report together (such as the PowerTap P1) you will see two power meter connections possible in the app. Select them both.
Either one can be set up to read cadence. It doesn't matter.
Need any help connecting your other devices? Check out this article: Device Connections
If you have any questions, or if your power does not seem to be reporting correctly, please submit a help request here.