I've never actually completed this game. So when I heard it was free on the app store, I wanted to pick it up again. As nice as it was to have a spindash in Sonic 1, that's really the only advantage I see on the mobile version rather than the original or even any other console ports. The controls are awful. This maybe just the fact I have big ass fingers, and I never got used to touch controls, but even without that, I just don't think the classic Sonic games were made for this control scheme, especially 1, given the fact that it's level design was made for you to be a little slower, and the added spindash/crouchdash makes it more awkward. Another thing is the ads. Now I know without the ads, it wouldn't be free, but these things pop up fucking everywhere, even when I push "start game". As for the game itself, it has it's flaws: the level design is honestly terrible for the most part, the boss fights are really bad and forgettable, and some of the game's physics are flawed as well. But there were some stuff that outweighed the bad, such as the music and the overrall game play. So I liked it enough to go back to it someday, just not on the mobile version.