Please try our education app - Math Blocks - designed to help young children learn basic math skill while being a fun speed game for all ages.  Unlike most math games, ours does both addition and subtraction (multiplication coming soon) and encourages you to solve a range of problems rather than just picking numbers that add up to one preselected number.  Please check it out at https://play.google.com/store/apps/details?id=com.mathblocks

Thanks

LFMSoftware
www.lfmsoftware.webs.com