Best free photo editing apps for iPhone?

I got an iPhone 12 Plus a couple of years ago to shoot video, but I always offload that and edit it on my computer; with doll photos, I often find myself wanting to edit (color, brightness, tone) but just too darn lazy to move things over. What are the best apps you use for doll photos on a phone?

 

I don't know if it's available for iPhone 12 Plus, but Focos. Focos, Focos, Focos. I swear by it.