I usually map myself a route with Google maps before I ride. Mainly to track my distance and time so I can figure my average riding speed to track my progress. But when I use my app on my phone to track myself for that ride, its very different from what Google maps is saying distance wise.

What app do you recommend using that you have found accurate? Or should I trust in Google maps and forget out the app.

Ps. Unfortunately I can not get a computer for the bike right now. So that's out of the question.

too many variables in your post to give you a decent answer. but I suggest using this site: https://www.gmap-pedometer.com/

it's accurate enough and easy to use

I recommend Ride with GPS. Requires free account, gives you good elevation/grade numbers, and you can export the route easily (can upload to many Garmin GPS devices). I've used gmap-pedometer for many years and like it too (although I like ride with GPS more).

Cheers,
Charles