OmniPDF is an Adobe Portable Document Format (Acrobat) file viewer for Mac OS X, OpenStep/Mach, and OpenStep for Windows 95/98 and NT 4.0.
OmniPDF is a very fast, intuitive way to view PDF (Acrobat) files. Try OmniPDF, and you will find it is an "invisible" app, that does what you need it to the way you expect it to.
OmniPDF allows you to select, copy, and save text in PDF files as ASCII or RTF. OmniPDF can save a 100-page document in seconds instead of minutes. There is no "text mode" or "hypertext mode", you can always both select text and follow hyperlinks.
OmniPDF allows you to search the text of PDF files. OmniPDF can search through an entire 100-page document in seconds instead of minutes. Once the file is indexed in memory, searches take less than a second.
OmniPDF supports thumbnails in a separate panel. The current page is always highlighted in the thumbnail panel, and clicking on a thumbnail selects its page.
OmniPDF supports PDF bookmarks using the standard OmniWeb bookmarks panel. Some others viewers use a browser, which is a less flexible widget.
OmniPDF displays text annotations in PDF files.
OmniPDF features good, fast font substitution for missing fonts, but doesn't stretch individual characters in the same font different amounts, which results in stems of different thicknesses which gives a "ransom note" look to the file.
OmniPDF follows hyperlinks within a PDF file, to other files on your local filesystem, and to URLs using OmniWeb.
OmniPDF changes the cursor to a little finger above links, and to an I-beam above text that can be selected. One can also hit space to see all links on a page.
OmniPDF outputs print jobs according to Adobe's Document Structuring Conventions (DSC 2.0), which Adobe's own Acrobat product doesn't. This is really nice if you are using Mac OS X's Preview.app, for example; OmniPDF allows you to go backwards and forwards through the printed PDF file and zoom in and out.
OmniPDF interprets PDF in Objective-C, rather than in PostScript. This makes OmniPDF fast and a little easier to control (especially on corrupt files) than PDF viewers that send PDF to the PostScript interpreter. Sending PDF directly to the PostScript interpreter is a security hole unless the PDF viewer first carefully checks the PDF file to make sure it contains only valid PDF commands. (Otherwise hackers could just put in any old PostScript commands and take over your window server.)
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.