From the topic, I'm curious that anyone here ever did the speed run on your phone? I'm planning to it, so anyone would interest to help me at it?

AFAIK no, i remember seeing on run potentially year ago, but i can no longer find it. Best bet would be to use the PSP route on the iOS version, and quicksave abuse during encounters/boss fights that go wrong. Theres an FF3 Speedrun Discord which has a lot of the current runners in there, probably the best place to ask any questions, albeit most of us are seemingly unfamiliar with iOS speedrun