When comparing Sumatra PDF vs Nitro Pro, the Slant community recommends Sumatra PDF for most people. In the question“What are the best PDF editors?” Sumatra PDF is ranked 5th while Nitro Pro is ranked 8th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Starts quickly
Pro Free and open source
Sumatra is available for free, licensed under GPL with source code available on GitHub.
Pro Low resource usage
Pro Does not have heavy editor features
Annotations and other heavy features are just not needed in reader.
Pro Extensive keyboard shortcuts
Pro Elegant interface
Pro Portable
The application consists of a single file that can be run without installation. You can put it on an external device, such as an usb thumb stick and run it on any Windows machine from the thumb stick.
Pro Multilingual
It's available in 69 languages.
Pro Nitro Cloud simplifies sharing, collaboration and getting documents signed
Nitro offers a cloud-service, called Nitro Cloud. Nitro can upload a PDF to the Nitro Cloud and notify other people via email that they can either view or edit a PDF or have to sign a PDF. If they need to sign a document they will be able to do it from the interface that's provided by the Nitro Cloud.
Pro Clean, ribbon-like user interface
Nitro Pro has an interface that will be immediately familiar to anyone who's used Microsoft Office products.
Pro Can directly convert Outlook e-mails to PDFs via a plugin
Single messages, conversations and folders can be converted.
Pro Good support for e-signatures
Nitro allows signing a document in three ways - using a webcam, writing it by hand or adding a signature from a file. It also allows you to send out files for signing via their cloud service, Nitro Cloud.
Pro Reasonable OCR capabilities
Pro Super-simple MS Office file conversion
To convert an MS Office file to a PDF, simply drag and drop the file on the Nitro Pro shortcut.
Pro Allows combining PDFs
Pro Allows batch printing multiple files
Pro Offers a trial version
Cons
Con Windows only
Con Lacking in features
Sumatra aims for simplicity at the expense of functionality. For example, there's no way to annotate PDFs or edit them.
Con Fonts are not smooth enough
Not as smooth as e.g. Adobe Reader. No anti-aliasing
Con Cannot crop empty fields
Just got used to this killing feature on Goodreader on Mac.
Con Pricey, bloated addvertising for nothing, frequent crashing
Nitro Pro is available for $140.
Con Difficult to register
Very buggy, no support.
Con Incomplete MS Office document to PDF conversion
Some attributes, like form fields don't get converted.