Could the title (andthe game for that matter) be more self-explanatory? No, probably not. Am I going to explain it anyway? Yes, indeed I am.
Ubongo is a fairly simple, but pretty nifty game that is, at its corea pretty much just a variation on tetris, but on a table instead of on a phone or computer. But, it adds in a few extra elements to make the game a little bit more interesting, since you're playing it with other people... I hope... (We've talked about this. Go make some friends, guys, please?).
Anyway, the objective in Ubongo is to take the pieces in the round (determined by the roll of a die) and get them to fit on your board in the exact way so that there's no empty space or pieces hanging off within the time allotted. (A good ol' hour glass hour glass is included in the box to keep time for ya!)
After completing the puzzle you have to yell "Ubongo!" and you'll then move your little piece along a track (1st place, up to 3 places, 2nd, up to 2, et cetera) to collect gems. Pay attention to where you're moving and what you collect because the person with the most of one color gem at the end is the winner (ties broken by next greatest amount of one color until there are no more ties).
Aaaaaaand, yeah, that's basically it. Yupp. That's the whole damn game. Like I said, it's pretty (ridiculously) easy. But, if you're bored of placing similarly shaped pieces alone on your computer screen, rally 1-3 other people and play a few rounds of this instead! (Then you can go back to your monotonous phone addictions and play as much tetris as you'd like).