QuickOffice back in June of 2012, and the assumption was that the product would be merged into Google Drive. It looks like that work is almost done. Google has said that in the "coming weeks", QuickOffice will be removed from the Google Play Store because the feature integration to Drive is done.QuickOffice has been around for quite a long time. The suite was first created back in 2002, well before any of the current smartphone platforms existed. Google purchased
If you already have QuickOffice, you can continue to use it, but it will no longer be updated, and new users won't be able to install the app from the Play Store. If you're looking for apps to handle editing of office docs, you'll have to stick with Google Docs, Sheets, or Slides, or maybe jump over to an alternative like the official Microsoft Office app.
source: Google Apps Blog