As a soon-to-be Model S owner, this thread was super helpful to me. Thought I'd bump it up with future owners. Thanks everyone!
I ended up ordering a card from every network out there that has one, and I downloaded all the apps. I think I ended up paying $20 total, with no ongoing subscription fees:
Blink - created account, ordered card, got app, no up-front payment
ChargePoint - created account, ordered card, got app, no up-front payment
EV Connect - created account, no card, got app, no up-front payment
Evgo - created account, ordered card, no app?, paid $5 up-front
Greenlots - created account, ordered card, got app, paid $5 up-front
PlugShare - created account, no card, got app, no up-front payment
SemaConnect - created account, no card, got app, paid $10 up-front