I’m wondering if training by doing reps of lunges could help. From a plank, can you place your foot between your hands as in pic?

Much better Sacha! Don’t worry about the back foot position, it doesn’t have to be on the pad all the time.

It is a good idea to focus on one thing. Or only one thing in the same part of the wave so they do not overlap (it can be one thing on the pop up and one thing when riding afterwards).

I screenshot what seems to be the biggest issue. See how much your weight is on the back foot right after the takeoff? You’re loosing all the speed that you got after going down the wave. Also notice that your arms are both on the same side of the board. I think that you can try to be even more front on and that would help for speed and stability.

You probably want to perform a bottom turn right after the takeoff, so I would say that you should look at where you’ll be in the middle of your bottom turn, that is, on the flats a bit in front of the wave, a few meters to the side from your takeoff point.

It looks like you are always pretty much extended and never compressed much. On a perfect front side bottom turn, your back hand should almost touch the water. This compression extension helps a lot to generate speed.

Sascha trust your peripheral vision. If you’re looking at the wave, you’ll see obstacles in time.

I know this French brand but did not try it: https://en.harnessmount.com/

It seems robust.

To turn, you’ll need to find the right sections on the wave. At the moment, you’re not looking even once at the wave. That would be the first next step, to twist your body in a way that allows you to look at the wave. Graham’s advice to get straighter will help for that.

In fact, looking at the wave should begin even before the takeoff, when you’re paddling to catch the wave.

You’re always going where you’re looking!

I’ll add to the previous answers that you must look at the wave while you’re paddling to catch it. Sure, with practice you’ll feel the right time to pop up, but if you’re not looking at the wave you cannot adjust your speed and positioning and that makes it more difficult to be at the right time and the right place.

Initially, I needed a surf coach to tell me which wave to choose and when to pop up. Surfing outside of the lessons, I catches way less waves. It will come with practice!

Maybe your phone is old and uses a version of Android that is not compatible with the last versions of the app and the last version compatible with your system is now obsolete.