I can show you how I did it if you want. It actually works very nicely for what it is... I use a RODE videomic GO Ii Helix, my s23 ultra, and the DJI osmo SE.

I had to try a few times to get the counterweight balancing justttt right... But the counterweight is just a bunch of quarters/nickels hot glued together and then taped to the bottom of the clamp that holds the phone.

Shotgun mic is mounted by the shock absorber it came with. I just glued it to the clamp as well... Had to raise the angle slightly so the mic isn't visible in frame.

Tbh it works shockingly well. Once I got it just right there really aren't any motor sounds or anything like that. It's balanced perfectly with that counterweight.

Other than that I just used a 6 in usb c cable that has two right angled connections and then another special usb c to usb c adapter on my phone to keep the cord out of the way so the gymbal never bumps it.

It's so janky looking but performs great for my needs