It doesn't get as much attention as the competition, but
SkyDrive OneDrive is a capable alternative to Drive or Dropbox. The Android app has been lagging behind on features a little, but today's update improves things. The new features help you stay in the app more instead of jumping to the browser to get links or manage content.
Here's the v3.0 changelog.
- Stream videos without leaving the app
- Add photos to albums
- Open share links in the app
The app probably should have had some of this before v3.0, but at least it's there now. A lot of phones come with free OneDrive promo space these days, so maybe you should give it another look. It doesn't hurt that the app actually adheres more closely to material design than Dropbox. Seriously, what is their deal?