Nimball Rewind, the protagonist is just a ball. It rolls and bonces around, but there's not much of an emotional connection there, if you know what I mean. But after all, this is a game, not a match-making service. And as a game, it's pretty darn fun!
Each level is quite short. A gripper arm drops you from the ceiling, and you need to roll and bounce until you reach your destination - a gripper arm resting face-up, that you can fall or jump into. In the screenshot you see me trying to leap into the gripper at the end of level 11. That square to the left is a "bouncer platform" (my name, not theirs). When you touch it, it launches you upwards. That can be a good thing, like here, or it can be quite bad, if the ceiling happens to be red. Red surfaces, in general, are "toxic" in this game - you're not allowed to touch them.
What happens when you do, though? This is where "time travel" comes in. Basically, rather than strike out, you can hit SPACE and rewind a bit, kind of like an Undo function [Hello, Braid... -Ed]. When you let go of the SPACE key, gameplay immediately resumes. But you don't get infinite retries, though: touch enough red walls, and eventually you'll have to start the level from the top. All in all, quite a fun platformer!
P.S: You can double-jump (jump while you're in the air). Took me a few minutes to figure that out.