1. Google Play Services
2. Gmail
Gmail team has also introduced another app, Inbox by Gmail, for android devices.
3. Google Maps
4. YouTube
5. Facebook
You can have information about your friends, see your wall, upload and download pictures, change your status, leave comments and a lot of other options that you can have on computer.
In addition to the facebook website, facebook messenger app is also available for android devices. Since January 2015, the amount of facebook app users reached up to 745 million every day.
6. WhatsApp
7. Google Play Music
8. Facebook Messenger
Facebook Messenger Lite has also been launched by Facebook. It is a fundamental app having limited features for low speed internet.
9. Google Drive
10. Instagram
Facebook acquired the Instagram service in April 2012 for about US$1 billion. In 2013, Instagram grew by 23%, while Facebook, grew only by 3%.