Question: what are most popular apps?
Answer: Facebook. Perhaps unsurprisingly, Facebook tops the list of the most-downloaded apps of the decade.
Facebook Messenger. Facebook chat was launched as a standalone app for iOS and Android in 2011. ... 
WhatsApp Messenger. ... 
Instagram. ... 
Snapchat. ... 
Skype. ... 
TikTok. ... 
UC Browser. ...