To continue using Nitro Pro after the trial period has expired, it is necessary to purchase a license that must be activated on your computer. Activation ensures that you have bought a genuine Nitro product by linking the software license to the computer on which it is installed.

The Insert Image tool lets you add images to your PDF files so you don’t need to go back and edit the original source file.

With Nitro Pro, you can use grids to assist you in precisely lining up links, form fields, and other objects on a page. When turned on, the grid is visible over your PDF pages; however, grid lines will not be printed when you print your document. You can also customize the grid’s display, setting preferences such as default units, line color, spacing, and other options.

The image arranging tools let you move images in front and behind other objects on the page, flip or mirror, and rotate them.

Just like attaching a paper file to another with a paperclip, the Attach File annotation tool enables you to attach electronic files to your PDFs files. Annotation attachments appear as a paperclip icon on the PDF page; reviewers can double-click the icon to open the file. You can view annotation attachments in the Commenting pane and the Attachments pane.

Repetitive tasks involving one or several documents can be automated with the Batch Processing tool.

Digital IDs let you encrypt files that can only be opened and used by people who have exchanged certificates. Certificate-based security has many advantages over password-based security: documents can be opened without the need to remember passwords, Digital IDs cannot be shared or copied easily, the one document can contain different security settings for each recipient of a file. For example, you may grant one person editing and printing privileges, while another is limited to just viewing the file.

Nitro Pro supports field calculations using several methods. The built-in calculation formulas are an easy means for creating simple, and quite restricted, field calculations. You can also use Simplified Field Notation and JavaScripts, although these methods are much more sophisticated and require some programming knowledge. If your calculation needs are limited to summing or averaging data, you can use the built-in formulas without having to worry about programming.

The Comments Pane gives you a centralized place to see and organize all of your annotations. It lists each comment, its type, reviewer name, date added, and the text included in any pop-up notes and text boxes.

The Auto Build Bookmarks feature can totally automate the creation of bookmarks in your PDFs, and with very little effort greatly enhance the usability of the PDFs you publish. Use it to auto-generate bookmarks based on the font styles (headings, chapters, etc.) and the layout used in your PDFs. You can also use it to build bookmarks based on the textual and numerical content of the PDF files by using the text masking and wildcards features.

You can create bookmarks by selecting text on a page and making it a bookmark, or by adding an untitled bookmark and then setting and naming it in the Bookmarks pane.

Of all the field types, button fields have the broadest use. You can add buttons on PDF forms to perform a variety of actions associated with filling out a form or you can use buttons on PDF documents not intended for form use. Buttons can be used for items in any PDF such as navigational tools in a PDF design, hyperlinks for a variety of different actions, and just about any other condition that sparks your imagination.

Radio buttons can be assigned the same attributes as check box fields. You use radio buttons more often for either/or responses. When you create check boxes you can uncheck a checkbox by clicking on it. The only way to uncheck a radio button is to clear a form or check another button that turns off companion radio button checkmarks.

The most common field type on PDF forms is the text field. Text fields permit respondents to add alpha text and/or numeric values. You can format text fields in a number of different ways to ensure fields are completed properly. You can add custom format scripts, validate data, assign actions, and perform calculations on text fields.

The document information fields in Nitro Pro are useful for users who want to know more about a document, and they’re particularly useful if documents are to be indexed. These fields can be used to help categorize documents and help narrow down search results from search engines and other indexes.

Whether you write scripts in your own documents, or browse files for scripts to examine, you first need to know where to look for JavaScripts. In Nitro Pro you can find JavaScripts in the following locations:

Nitro Pro lets you view all comments in your PDF file from a single location. The Comments pane lists all of the comments in your file, along with information relating to each comment.

The drawing tools in Nitro Pro allow you to add predefined shapes (for example, lines, rectangles, or ovals) as well as free-form drawings to your PDF documents. These drawing tools include a corresponding pop-up note, enabling you to provide additional comments or further explanation for each drawing. You can also change the appearance of your drawings, with options for color, opacity, pointer styles, and more, depending on the type of drawing you use.

The Measure tool enables you to easily define the distance, area, and perimeter for a set of points based on a scale that you define.

Microsoft Rights Management (RMS) provides a service that protects and shares files by allowing you to encrypt your sensitive documents and restrict access to approved individuals only.

Stamp annotations let you add editable stamps to pages as annotations. The built-in stamps (such as Paid, Reviewed, and Approved) give you a simple means to indicate the status of a file. Using the custom stamp feature, you can type your own text to create a stamp, or use any image or PDF file into your own stamp.

You can add links manually to your PDF pages by clicking the Link tool and drawing the outline of the link on the page. Once it’s added you can edit its appearance and set the action it should perform when clicked by the user.

Simplified field notation is written more like formulas you add in spreadsheet applications like Microsoft Excel. Writing a notation is often an easier solution when adding calculation scripts.

Any form you create that requires calculations is likely to require custom calculation scripts. The options you have available with preset calculation formulas are limited to simple multiplication and addition. Other kind of calculation you need requires writing a script.

Folder level JavaScripts are JavaScript files (.JS) that are run during application startup. These can be useful for loading reusable JavaScript functions into the application, or accessing methods/properties whose security restrictions only allow them to be run in the app/init event.

You can use JavaScript to add an almost infinite number of interactive features, create complex calculation formulas, and add more dynamic functionality to your PDFs.

Just as you would with a paper document, you can place notes and write annotations anywhere in a PDF file. Notes let you direct the attention of readers to a specific area of the page, and to include special instructions for a person reviewing the document.

When viewing or editing a PDF document, you can adjust the zoom level by using the following tools:

Nitro Pro features mark-up tools to help you draw attention to text that requires revision. These tools are a useful way to combine feedback or comments with every mark-up.

A static object that represents the PDF viewer application.