Website: http://digitwhiz.com/
Free iPad app: http://itunes.apple.com/us/app/digitwhiz-math/id559968556?mt=8&uo=4&at=10l6SU
Website: https://www.xtramath.org/
Free iPad app: http://itunes.apple.com/us/app/motion-math-hungry-fish/id483049169?mt=8&uo=4&at=10l6SU
Free iPhone app: http://itunes.apple.com/us/app/motion-math-hungry-fish/id483049169?mt=8&uo=4&at=10l6SU
Website: http://www.sumdog.com/
Free iPad app: http://itunes.apple.com/us/app/motion-math-zoom/id451793073?mt=8&uo=4&at=10l6SU
Free iPhone app: http://itunes.apple.com/us/app/motion-math-zoom/id451793073?mt=8&uo=4&at=10l6SU
Paid iPad app: https://itunes.apple.com/us/app/motion-math-hd/id410521340?mt=8&uo=4&at=10l6SU
Paid iPhone app: http://itunes.apple.com/us/app/motion-math/id392489333?mt=8&uo=4&at=10l6SU
Edmodo app: http://www.edmodo.com/publisher/motionmath
Free iPhone app: https://itunes.apple.com/us/app/geoboard-by-math-learning/id519896952?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/geoboard-by-math-learning/id519896952?mt=8&uo=4&at=10l6SU
Website: http://www.mathlearningcenter.org/web-apps/geoboard/
Google Chrome app: https://chrome.google.com/webstore/detail/geoboard-by-the-math-lear/gaakmmdiopnmcenkojohldanladpajak
Free iPad app: https://itunes.apple.com/us/app/number-pieces-basic-by-math/id611452042?mt=8&uo=4&at=10l6SU
Website: http://www.mathlearningcenter.org/web-apps/number-pieces/
Free iPad app: https://itunes.apple.com/us/app/number-pieces-by-math-learning/id605433778?mt=8&uo=4&at=10l6SU
Google Chrome app: https://chrome.google.com/webstore/detail/number-pieces-by-the-math/fhcpnppigjdhghbohcbogmmhmfkobgbm
Website: http://www.mathlearningcenter.org/web-apps/number-pieces/
Free iPad app: https://itunes.apple.com/us/app/number-rack-by-math-learning/id496057949?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/number-rack-by-math-learning/id496057949?mt=8&uo=4&at=10l6SU
Google Chrome app: https://chrome.google.com/webstore/detail/number-rack-by-the-math-l/pdblapgbfbphhldogcijidlkbcgokfkc
Website: http://www.mathlearningcenter.org/web-apps/number-rack/
Free iPhone app: https://itunes.apple.com/us/app/mathtappers-find-sums-math/id353582286?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/measure-length-tiny-chicken/id523542924?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/measure-length-tiny-chicken/id523542924?mt=8&uo=4&at=10l6SU