Things of note:
1: If you reach the highest point on the map you win.
It would've been nice to know this from the start of the game, it wouldve made me waste less time just playing around.
2: The game looks very bare, like a test version of the game rather than the actual game
3, and most importantly, it was enjoyable while it lasted. If the game is developed a bit more it could become very enjoyable. Add some time counters, multiplayer mode to compete with other players, yada yada yada... and I would rate it very well.
For now, though, it feels like a 3 stars game to me.