Computer and mobile games are being used as a tool to increase students’ productivity and efficiency. It is necessary that educational games should be in balance with the elements of game and knowledge. However, it is not clear what features in these two elements that should be in place to produce an effective and efficient educational game. To address this, a study was conducted to evaluate four android mobile games based on different educational subjects. The target group of this study was school children age ranging from 7-12 years. A questionnaire was formulated based on heuristics for educational computer games. 58 participants participated in this study. The study results reveal that educational mobile games have potential to improve students’ productivity. Even though knowledge and fun features should have a proportionate balanced, the game should not drop the essence of fun and entertainment. This study also suggests a framework for developing educational games should be created in the future.