What's Missing is a free Android game developed by FunGyan. The game is a simple and fun way of learning number and alphabet sequencing. The player can move to the next level by completing the minimum number of correct games. The game shows the player's statistics after each game, such as the number of wins and winning percentage, which encourages the player to keep going for higher achievements.

The game is easy to understand and has 12 levels with increasing difficulty. The game also features a voice on each alphabet/number button, and the option to mute the sound is also available. In addition, the game has options to select playing with only numbers or alphabets, and it supports all screen sizes. Overall, What's Missing is a great app for anyone wanting to improve their sequencing skills in a fun and engaging way.