Operating System HW

· https://techcrunch.com/2015/08/11/its-operating-systems-vs-messaging-apps-in-the-battle-for-techs-next-frontier/

· https://mashtips.com/crossplatform-messaging-apps-mac-windows-ios-android/

· http://searchmobilecomputing.techtarget.com/tip/Comparing-mobile-operating-systems-and-application-environments

· https://en.m.wikipedia.org/wiki/IOS

· https://www.androidpit.com/battery-draining-apps

· https://www.diygenius.com/best-educational-iphone-apps/

· https://books.google.com/books?hl=en&lr=&id=zZcpuMRpAB8C&oi=fnd&pg=PR7&dq=iOS+interaction+with+apps+ios+OR+apps&ots=UuLd81q74c&sig=upNsS9nVLrbXm4jCDCEufZSUPMg#v=onepage&q&f=false

· https://en.wikipedia.org/wiki/ESPN

· https://netflix.github.io/

· https://en.wikipedia.org/wiki/YouTube

· https://developers.soundcloud.com/blog/page/3.html

· https://books.google.com/books?hl=en&lr=&id=dbA_AwAAQBAJ&oi=fnd&pg=PR9&dq=iOS+interaction+with+apps+ios+OR+apps&ots=HWwIvkI_bR&sig=RV6t4T_1lLXjXqzQTbQe6SuHXbA#v=onepage&q=iOS%20interaction%20with%20apps%20ios%20OR%20apps&f=false

· https://en.wikipedia.org/wiki/Khan_Academy