I want to record myself drawing so I can speed it up and put

Shower curtain rod, coat hanger, and either some rubber bands or string.

>>17248151
You need something to hold and stabilize the phone.

What's your budget?

>>17248161

£100

https://www.youtube.com/watch?v=7lC7I0FNsy4

>>17248164
Lotta makeshift ideas you could use. Construct a drawing cube rig with support slats on too for phone balancing.
Use a smart.phone compatable tripod camera mount end and secure it to a structure, etc etc.

Google Image search "camera shooting straight down" for product ideas and lighting placement

Grab a TERTIAL desk lamp from Ikea: the kind that clamps to a desk or table, then mounts the lamp onto a boom arm. Remove the lamp, and use rubber bands to fasten the phone to the arm. Voila: an adjustable boom mount for about a tenth of your stated budget.

Some people use this technique to mount Webcams, and you can even mount light cameras this way. I do too, but I've had to use it with a phone once or twice, so I can verify that it works.