If you need help factoring, you should check out this app. This will take any expression up to x-cubed and show you how to factor it. You simply enter the equation and it'll take you through factoring it, step-by-step.
Once you feel like you've got the hang of it, you can try out test mode. You pick the types of factoring questions and how many questions should be on the test and it does the rest. In order to pass you must get each problem correct or you'll start over.
There's also a quick check mode, which is perfect for doing your homework. You can enter the problem, enter your answer, and it'll tell you if you're right or wrong. If you're wrong it'll give you the option to show you the steps.
You can download it from the iTunes store by clicking here