Since then, Google made Quickoffice free (first for business users, then for everyone), removed integration with other services than Google Drive, improved Quickoffice's interface, created a Chrome extension for editing Office files and added native Office editing to the new mobile apps for Docs, Slides and Sheets.
Now Quickoffice will be discontinued and the mobile apps will be removed from Play Store and App Store. "With the integration of Quickoffice into the Google Docs, Sheets and Slides apps, the Quickoffice app will be unpublished from Google Play and the App Store in the coming weeks. Existing users with the app can continue to use it, but no features will be added and new users will not be able to install the app," informs Google.
