Apps not specific to subject/grade.
Website: http://www.sketchlot.com/
Website: https://www.smore.com/
Paid iPhone app: https://itunes.apple.com/us/app/tubeplayer/id561917679?mt=8&uo=4&at=10l6SU
Paid iPad app: https://itunes.apple.com/us/app/tubeplayer/id561917679?mt=8&uo=4&at=10l6SU
Free iPhone app: https://itunes.apple.com/us/app/tubeplayer-free/id561918592?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/tubeplayer-free/id561918592?mt=8&uo=4&at=10l6SU
Website: http://www.storyplanet.com
Free iPhone app: https://itunes.apple.com/us/app/action-movie-fx/id489321253?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/us/app/action-movie-fx/id489321253?mt=8&uo=4&at=10l6SU
Free iPad app: https://itunes.apple.com/book/ipads-in-the-classroom/id593799531?mt=11&uo=4&at=10l6SU
Website: https://www.accredible.com/
Website: http://www.biteslide.com/
Website: https://www.mindmup.com/
Google Apps for Education app: https://apps.google.com/marketplace/u/0/app/mkgkheknpfngchmoaognoilfanomldfl
Google Chrome app: https://chrome.google.com/webstore/detail/mindmup-20-free-mind-map/mkgkheknpfngchmoaognoilfanomldfl
Website: https://beta.mural.ly/
Google Chrome app: https://chrome.google.com/webstore/detail/murally/nnhlnnalackljjehlfocmheepffkiihf
Website: https://www.biodigital.com/
Free iPad app: https://itunes.apple.com/us/app/biodigital-human-3d-anatomy-and-disease-models/id771825569?mt=8&at=10l6SU
Google Chrome app: https://chrome.google.com/webstore/detail/biodigital-human/agoenciogemlojlhccbcpcfflicgnaak
Free iPhone app: https://itunes.apple.com/us/app/biodigital-human-3d-anatomy-and-disease-models/id771825569?mt=8&at=10l6SU
Website: http://www.commoncurriculum.com/
Paid iPhone app: https://itunes.apple.com/us/app/bridge-constructor-playground/id578203499?mt=8&uo=4&at=10l6SU
Paid iPad app: https://itunes.apple.com/us/app/bridge-constructor-playground/id578203499?mt=8&uo=4&at=10l6SU
Paid Android Phone app: https://play.google.com/store/apps/details?id=com.headupgames.bridgeconstructorplayground
Free Android Phone app: https://play.google.com/store/apps/details?id=com.headupgames.bridgeconstructorplaygroundfree