You can now keep up to 1000 EPUB or PDF files in Google Play for free. You're able to upload from your PC or import from Google Drive available to read anywhere.
Here's Google with the announcement:
Upload your personal documents to Google Play, and read them anywhere.
- Keep up to 1000 EPUB or PDF files in Google Play for free.
- Upload from your computer or import from Google Drive.
- Read anywhere: in the web browser, on Android phones and tablets, or with iPhone, iPad, and iPod touch.
- Page position, bookmarks, and notes are synced to the cloud, so you can pick up reading where you left off.
File size can't exceed 50MB, and it may take a few minutes to finish processing before you can read. You can find out more and try it out for yourself at the Google Play website.