This has all the key functionality of being a game: player movement, a goal, obstacles, and last but not least, tracking your score ;p
The player movement is smooth and feels good. I like the warning for the obstacles before they come. I find it interesting the horizontal obstacle can slide diagonally (relatively) if you are moving up to the next level - it provides a little challenge to the player when they think they're safe.
With ramping difficulty, even as simple as more (but fair) obstacles. Or maybe to the next level you go across or back down. The game feels good to play, even when "simple", which makes adding polish a bit easier.