There's an app called DoubleMap that you can use to map your bus and see all the routes, but there's no B-Line or BCAG app currently.
You can download the DoubleMap app from the Google store. Select Butte Regional Transit and it will display all the B-Line bus routes and stops along with real-time location of the buses so long as the bus is connected to the system. Sometimes it doesn't. The B-Line website is also mobile friendly with all the bus schedules and maps.
Thanks! Your answer is awaiting moderation.