PDF eraser is an application which will help you to remove unwanted objects like text, images from PDF files. It also supports adding text and images to a PDF file.
To erase objects from a PDF
Open the PDF file, and select Eraser size from small, medium and large and erase the unwanted things and save the PDF
To Add Text and Images to PDF
You can use Add Text button , after typing you can choose the color, font and size of the text
Use Add Image button and select the image you wanted to add to the PDF file.
This application can remove unwanted pages too using the the Page Cutter option.
This application id Free for every one, but will add a watermark on the PDF. To avoid this you will need a PRO version of PDF Eraser, which will costs $29.95 normally. For a limited time the developer of this product is giving away the PDF Eraser Pro full version license for free.
You can get the key from this giveaway page
Last date to get it is September 15 , 2014.