Your Android smartphone is like a miniature computer in your pocket, giving you much of the same access to files, folders and documents that you would typically have on a full-sized device. There are a variety of ways to read PDFs, for example, many of which also enable annotation -- in other words, adding a comment, explanation or sketched markup.
You can view and annotate PDFs on your Android using a mobile version of the same Adobe Acrobat software you use on your computer. In addition to its viewing capabilities, the app features a number of built-in annotation features. You can highlight, strike through and underline text, add sticky notes anywhere in the document and even add text within the PDF's content itself. With the freehand drawing tool, you can add hand-drawn sketches with the PDF as well.
A Mobile Office App
An office document app like Polaris or QuickOffice can be used for both viewing and annotating PDFs. One of the two applications is usually preinstalled on Android devices, though QuickOffice is also available for free in the Google Play Store. With the PDF document opened in Polaris, tap "Options" and select "Annotations On" from the menu. From there, tap the quote bubble icon to be presented with available annotation tools -- like highlighting, shape-drawing and commenting. QuickOffice functions similarly -- with a file open, tap the "Annotate" pen icon and select the type of annotation you wish to implement.
A Third-Party App
Third-party PDF apps may offer more sophisticated annotation tools for your needs. With the Repligo app, for example, you can highlight a line of text and then long-press it for more options -- including strikethroughs, underlining and sticky notes. The ezPDF Reader app also offers highlighting and notating, though it is known for its doodling capabilities. There are, for example, a variety of pens and colors available for implementation. With the Skitch app, on the other hand, you can doodle on an opened PDF and then embed arrows, shapes and other stamps onto the document.
There are also Web-enabled solutions that allow you to annotate PDF without a separate app -- and also implement collaboration by way of an online workgroup where you can upload and annotate documents that can be seen by all users in real-time. Solutions include A.nnotate, PDF Online Reader and Group Docs. Simply upload the PDF from within your device's browser, then add annotations, highlight text and save in-file notes so they are available immediately to anyone given permission to access the document.
- Adobe: Adobe Reader Mobile App
- HongKiat: 20 Free Tools to Annotate PDF Documents
- Tech Bush: 4 Best PDF Readers for Your Android Device
- PC Mag: Polaris Office 4.0 (for Android)
- HTC: Highlighting and Drawing in Pen-Integrated Apps
- TMobile: LG Optimus F3 Preinstalled Apps
- Google QuickOffice Support: QuickOffice Icons
- Android Spin: Evernote, Skitch for Android Updated With PDF Annotations
- YouTube: Annotate Highlight Draw on Your PDFs With ezPDF App
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