RepliGo Reader is also very good, and I believe it is the engine behind PDF to Go.
Originally Posted by raja_3012
It is very strange that you can view PDF's (without any 3rd party tool) attached with a mail but cannot view the same attachment if it is saved to a drive. Would anyone know the logic behind it?
When a PDF file is attached to an email, the attachment resides on RIM's servers until you open it. When you open it, RIM's servers actually process the file and send a JPG image of each page to your device. Without third party software or the aid of RIM's servers, your device has no ability to process a PDF file.