This is a list of my favorite math apps for mobile devices.
Website: http://www.khanacademy.org/
Free iPad app: https://itunes.apple.com/us/app/id469863705?mt=8&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/id469863705?mt=8&at=10l6SU
Free Android Phone app: https://play.google.com/store/apps/details?id=org.khanacademy.android
Free Android Tablet app: https://play.google.com/store/apps/details?id=org.khanacademy.android
Edmodo app: https://spotlight.edmodo.com/product/khan-academy,324527/
Free iPad app: https://itunes.apple.com/us/app/thinking-blocks-addition/id668450919?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/thinking-blocks-multiplication/id669725575?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/thinking-blocks-fractions/id670767677?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/thinking-blocks-ratios/id670448325?mt=8&uo=4&at=10l6SU
Paid iPad app: http://itunes.apple.com/us/app/factor-samurai/id441919897?mt=8&uo=4&at=10l6SU
Paid iPhone app: http://itunes.apple.com/us/app/factor-samurai/id441919897?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/fast-facts-multiplication/id483585965?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/fast-facts-multiplication/id483585965?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/fast-facts-division/id488453350?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/fast-facts-division/id488453350?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/mathtappers-multiples-math/id371520443?mt=8&uo=4&at=10l6SU
Website: http://www.studystack.com/