Great price.
If you own a vehicle, definitely worth the buck.
Has a lot to offer with the free version. No you do not need to pay to use the piece, though should you want live and human interaction on the app, then yes you can pay like 2-3$ for the first year per month and get help.
Or use this little piece and Google or look on the app what the issue is.
I own two of them and just ordered a 3rd. Really solid piece to own.
https://www.fixd.com/3tg/ship1-sensor