I need some good mobile games to run that are no longer than 20 minutes long. Any recommendations?

cat bird

Here’s some.

https://www.speedrun.com/speedrunning/thread/kkioc/1

dadish, super cat tales, bomb chicken, leap day, dadish 2, supercat tales 2

Rodeo stampede

You could try the mobile version of "Robot Wants Kitty" (which is a different game from the old Flash version from 2010):
https://www.speedrun.com/rwk_mobile

But it's probably easier to play on the web version of it.

TING

A mobile RPG Text game in which you can make several types of Speedruns, it is simple, direct, requires good memory of the player, good tactics and of course good RNG. The game usually takes more than 1 hour to complete, but speedruns can be done under 30 minutes. This is the link:

https://www.speedrun.com/life_in_adventure