Now that Apple's iPad has become popular, many users will want to view PDF files on the go. With a brilliant screen, e-books and documents display beautifully on the iPad.

So, do you need a good PDF Reader App to view PDF's on your iPad? If you do not know which pdf reader app is suitable for you, I will tell some good pdf readers for you here.

iBooks
Apple's native e-book reader is perhaps the worst choice for in-depth PDF reading. Although the app recently gained the ability to include PDFs alongside e-books, its features are still severely limited. The interface is the slowest among all the apps we tried, taking up to two seconds for a single page to be rendered (an instantaneous action on better readers), and you have no way to highlight, annotate or copy any of the text from the PDF. The search function works well, giving you access to Wikipedia and Google for a Net search if needed, but it kicks you out of the 'iBooks' app and into Safari instead of doing the search in-app. We'd only recommend 'iBooks' for the most casual of PDF readers.

E-book Readers
iPad e-book reading apps such as iBook, Stanza, Kindle and Nook can handle PDF documents as well as e-book formats. Features on the PDF reader are limited compared to the e-book format, but you can pinch zoom to resize the text for easier reading. Some apps also offer in-app brightness or contrast adjustment so you can set the background and text contrast at a level that is easy on the eyes.

PDF Readers
The iPad App Store is full of PDF readers with various features, including the ability to mark up PDFs or add signatures and fill in forms. Each reader's features are explained in the store's deion, so check out several options before you settle on a specific one. Look for one that allows color and contrast adjustment, one and two-page layout views, zoom and search features.

iAnnotate PDF'
iAnnotate PDF' is like the PhotoshopCS5 to the other apps' MS Paint. In fact, it may suffer from too many features, with a zillion helpful pop-ups for every page and tool. Thankfully, once you've worked your way through the app's myriad options, you can turn off the help windows, and customize the interface within an inch of its life. It sports dynamic highlighting, a pen tool, notes and bookmarks, all of which can be saved to the file so that they can be read in any PDF reader on any device.

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