How do I go about triggering a background task to occur when a user opens the tile on the band while the phone app is suspended?
Alternatively, how would I make my background task constantly listen for the TileOpened event?
On Windows (Phone) 8.1, background tasks cannot be triggered by ad-hoc input from a Band. To receive events the application must be running, either in the foreground or background, with an active connection to a Band, and with a subscription to a Tile event.
Background tasks on Windows (Phone) can only be triggered at most every 15 or 30 minutes, which means that they are not generally suitable for polling for Tile events as it's unlikely they will be running at the time the user opens a Tile.