I have been enrolled in Recurrent's program for about a year. For those who are not familiar, it uses APIs to tap into your OnStar data. The primary intent is to do long term tracking of battery degradation, and secondarily the reports could benefit you when trying to resell the EV by disclosing the health of your pack, sort of like a Carfax report. You can
enroll here.
When you sign up, it prompts you to login to your MyChevrolet account, then they get a token from GM enabling them to access the data without requiring your credentials. So, it is secure.
I am also participating in another program with another vendor that intends to tie in with utilities. The OnStar APIs allow control over charging for demand-response, monitoring charging activity for Time of Use, etc. It also works the same as far as enrolling.