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One thing I am realy missing on the Tesla app is the ability to search a Map location on my phone and send it to the tripplanner and be able to see what superchargers it would hit etc on my phone. I guess that would be something to add to the wishlist.....
Create a calendar entry on your phone from the map. Then sync your calendar with the car. Open the calendar on the car and select your entry. It will navigate to that location and choose chargers along the way to get you there.
I'd pay $5 for such an app, or even a donation too. A one time lifetime payment is definitely preferred but if the subscription fee was a decent amount I would maybe do it, just because I don't take that many road trips and I could just use the website or use the Tesla built in one (The app would be like a second opinion).
The one or two trips a month limitation would honestly kind of be too limiting, just because I personally like to plug in different destinations and play around with the trip planner to decide on a road trip destination. A two trip limit would just be a single round trip.