Simple game principle of fun

The rules are quite simple. On a pitch (4x4 boxes) fields can be populated with numbers. It is possible these fields to move horizontally or vertically. Meet two numbers the same level, so "merge" them only a number, but has twice the height. Simultaneously, a new field is filled with either a 2 or a 4 in each train. The goal is to reach the number 2048. Sounds complicated, but it's not at all. There is a lot of fun, I'm really very pleased with the game idea and the implementation.