If you've ever had to view PDF documents, there's a good chance you're already very familiar with Adobe's Acrobat Reader. After starting off on Windows and Mac platforms back in the 1990s, Acrobat Reader arrived on Android devices in 2010. Even after the arrival of plenty of competing options, Acrobat Reader has managed to remain popular and has now hit a milestone of over 500 million installs on the Play Store.

PDFs improve our personal, school, and job-related workflows by doing several things right. Document formats are maintained when shared, format is ubiquitous, non-text elements can be easily integrated, file sizes are relatively small and respond well to compression, and PDFs work on any operating system. With continual updates to the app, users can also use it to sign documents, add annotations and sticky notes, easily convert PDFs to other formats, and store files in the cloud for easy accessibility. Upgrading to a paid subscription unlocks even more features.

If the app isn't pre-installed on your phone already, go ahead and give it a shot at the link below.