If you are interested in developing your own application for use with SB20, you may review the Fitness Machine Service (FTMS) Bluetooth specification, which "exposes training-related data in the sports and fitness environment, which allows a Client to collect training data while a user is exercising with a fitness machine (Server)."
With this specific information, your application will be able to receive power, cadence, and control the SB20.
If any further information is needed, please submit a new ticket with Stages Customer Service.