Platform 16 Beta 2 (Sep 21, 2018). Please donate.
400+ real apps, New: Qmmp (Oct 12, 2018)
Over 770 million app downloads
Any idea of online sites I can do this
Although this site caters to software for personal computers, your best bet would be Google drive or a similar like service, Dropbox etc. There are hardware type backups like wifi enabled HDDs and flashdrives, but I'm not familiar with those.