Review Foxit MobilePDF
A good reader of PDF documents
Author: Tariq Abdulla
Date: 28 Aug 2016, tested on HTC One S
Simple interface, minimalist design, completely free
Foxit Mobile PDF Reader for Android is a swift little PDF reader with neat little features to set it head and shoulders above the rest. You can even sign PDFs with your finger. Pretty cool.
Foxit Reader is going to find all PDFs on your device; no doubt mostly in your Download folder. It has options to list folders with the numbers of PDFs in them, or just show all the PDFs you have. This saves you from searching around for things too much. It gives you little thumbnails of your PDFs which is handy for quickly sorting your comics from your tax return.
There are banner ads in the free version. They are small, but if that's going to annoy you, you might stick to your stock reader.
It seems like it can annotate PDFs, but honestly I just couldn't seem to figure out how to use that feature. It's got a "share" button for quickly emailing the document, or sending it to Dropbox or whatever. It has a decent zoom, that will make reading things on a small screen as pleasant as possible.