Platform 15.0.2 (May 17, 2018). Please donate.
300+ real apps, New: KeePass Pro 2.39 (May 09, 2018)
Over 970 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.