Mathway is the best math app to solve mathematical problems on your android device. As a math calculator it provides instant solutions to most problems that may bother you and teaches you how to do it by yourself in future.
With huge variety of options available solving problems in basic math, algebra, trigonometry, precalculus, calculus, statistics or chemistry. All you need to do is enter the necessary values or input a pic shot with your camera and Mathway will proceed with step by step explanations. Neat feature is the creation of complex graphs to visualize solutions.
Some kids and grown ups can use Mathway to cheat, but in fact any great learning tool can be turned into a weapon. Just put your equation and lets it show the solution.