A free app for Android, by 360Documents.
If you are someone who has to manage documents on a daily basis, or if you work with a lot of them, then this app is the perfect solution for you. With it, you can easily view and edit all kinds of document formats, including PDF, DOC, DOCX, XLS, XLSX, CSV, PPT, PPTX, PPS and PPSX. It also supports many other formats, so you can open and view files from different sources, such as email, FTP, and even local storage. You can also print and share PDF and DOCX files with this app.
To use it, first, install the app on your device. Then, open it and log in with your Google account. It will then detect the files on your device and open them for you to view. You can view and edit the PDF files right away, but if you want to view or edit other types of files, you will need to download them as well.