I think its time to update this tread...
Forget the app mentioned unless u want malware or your info stolen etc.
U can't enable SC with an app lol
SC/DC parameters are in the gateway and u need either Root, Toolbox2 or Toolbox3 Service Center version (the one sold to public won't work)
Contact
@LayZ for root/SC/DC, he did mine remotely fairly easy n quickly, for a price of course
Keep in mind that Tesla can still disable SC/DC from the Supercharger itself even if you're offline so do it at your own risk or just stay away n use DC.
Some new cars come with CCS hardware/setting enabled and just need an adapter. Legacy cars need retrofit installed first.
Updates and Tesla App works just fine for Salvage cars, i got a recent update myself. (Edit: i should clarify, it works on Salvage cars not sure about Rooted cars)
I hear FSD/EAP n such features also stay n tied to the car.
Search is your friend, many treads about these issues...
Be smart n enjoy the awesome car!