An excellent remake of the original game! I'm quite the stunned it plays so well on Mobile devices. It contains a lot of content for you to enjoy, including Knuckles in Sonic 2 to play off the bat. The ad's aren't that annoying, but if they really bother you than you can get an ad blocker or turn off your Wi-Fi. The gameplay is the same as the original, which still holds up nicely, and the music is still outstanding. Thank you Christian Whitehead and HeadCannon!