- The first notable change is that it's widescreen (which may be the only way Sonic 3 will ever be in widescreen as Sega insists on never remastering Sonic 3)
- 60 FPS without slowdowns
- Controller support (it's not emulation despite it needing the ROM, so it's worth pointing out the controller support)
- you can control Tails like in Sonic Mania
- option to prevent outrunning the camera
- achievements are added and unlock some secrets (from what I can tell a Knuckles and Tails mode and the drop dash from Mania are unlocked)
- you can select new level layouts or the original
- skippable cutscenes
- option to pick a remastered soundtrack or the original
- you can pick some music to be from Sonic 3 or Sonic & Knuckles
- a few optional difficulty changes
- free roam any level from the beginning
- time attack mode
- mod support