Emanuele Feronato writes: "Hop Hop Hop Underwater is a game developed by Ketchapp you can find both on App Store and Google Play.
In the game you control a character which can hop above and under the water.
When above the water, you must tap to jump. When underwater, you must tap to dive.
We can build a HTML5 prototype in a few lines using Phaser, this way ..."