I have a Pixel 4a and it heats up a little playing Balatro, but all of the below it has no issues with:
Flipflop - a fun take on solitaire
Downwell - a vertical platformer
Holedown - an inverse breakout, minus the paddle
Desert Golf - a true indie classic!
Radiant - a Galaga/Space Invaders-ish shmup that's old enough to probably be lightweight these days.
anything by Kairosoft - a developer of sim management games I've been playing games from since I had a flip phone. Just find a theme you like and go crazy.
NYT games - They have more than Wordle! Connections, a word grouping game, in particular is fun, and so is Strands a themed word search. They're all updated daily for free on one app. They just lock off previous days' puzzles and the crossword. (Though they have a small quick crossword that's also fun.) It's actually discounted right now for an actual subscription
Reigns - I found this very fun. It's not for everyone. It uses Tinder's swiping to let you make decisions and try to run your kingdom. Good luck.
Prune - a puzzle that that relies on pruning your growing plant to reach the goal
80 Days - a narrative game with a decent amount of reading, as you attempt to buy, sell, and barter your way through your adventure.
Crossy Road - Frogger-inspired game with more maps and more fun.
Plague Inc - also a classic. Control a disease as you attempt to infect and destroy humanity. (This was popular before COVID.)
Burrito Bison - time your taps to launch your lucha libre across the map.
Super Mario Run - just simple enough to make you mess up sometimes. But it's not bad. I liked it.