I noticed the same thing when I tried the app. I did call the 800 number and it was for Ram connected services. I'm the 2nd owner and the app subscription was still under the original owners name. In order for me to transfer everything into my name, I had to pay for the subscription. Once she told me that, I didn't even ask how much it is and hung up the phone. I can remote start and lock/unlock with my key fob. However, not having the keys on me and needing something from the truck would be a nice feature but not worth a monthly fee to me.
I think those that bought new are the only ones who can still use some of the features once the trial and/or subscription runs out.