Android: Google Drive on the web comes with a ton of awesome and useful add-ons. Now, that power’s coming to Android. When using Docs or Sheets, you can install a selection of add-ons built specifically to extend the mobile apps’ functionality.
Google has been running a preview program to let developers build add-ons for its Docs, Sheets and Forms productivity tools since 2014. That option has now been opened up to all developers.