Android Mobile Devices come with a stock standard PDF viewers built in that allows any user to download, and view PDF documents. But there are always users who want more, functionality, power and just apps in general.
Popping PDF Reader into the Android App Store search bar revels 48 results.
The majority are free, with some ranging from AU$1.00 AU$19.01. Let's focus on the free for now though, and we can follow up with a paid PDF app article at a later date.
FoxIt have a reader which a robust range of features that turns it into a bit of a mobile PDF editor. Called FoxIt Mobile PDF, and listed in the productivity section there is a range of features within each function of the product. It has 4.3 stars and has been installed on 100,000 – 500,000 devices
View PDF documents
Annotate and comment on PDF documents
Outline / Bookmark / Annotation management
Public cloud integration
There are so many viewers, readers and editors it can be tricky. All have their problems so it is important to know what you want the app for, make sure it has the feature and to read the reviews so you know what to expect. Adobe and FoxIt seem to be the best at this stage in the game.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.