Premium WordPress plugins provide extended features and customer support not available in top free WordPress plugins. Most of the premium WordPress plugins are used for commercial projects (check out also ecommerce WordPress plugins). This review includes premium WordPress plugins which are used to increase number of blog subscribers, manage ad sales and display, operate affiliate programs, flexibly customize every page or make it look as native iPhone app, optimize the content for SEO and increase Google traffic. The cost of these premium plugins varies but it will pay off very quickly. If you need a powerful custom solution, you can rely on one of these great plugins for WordPress.

Ninja Affiliate
MaxBlogPress Ninja Affiliate automatically converts any keyword in your blog to an affiliate link. You can also cloak your affiliate links using redirects, use nofollow tag, track them and manage them right from WordPress.

Gravity Forms
Gravity Forms is advanced and flexible contact form plugin for WordPress. It features conditional fields, inline HTML content, option for users to submit posts and upload attachments, visual forms editor and many other.

Popup Domination
PopUp Domination is a premium WordPress plugin to build up your subscribers list. It works by adding a popup lightbox to your blog or website which can dramatically increase (double or triple) the opt-in rates to your email list.

Impact Page Template Plugin
Impact is a premium WordPress plugin that allows you to create an unlimited number of totally custom page templates. You’ll have control over the appearance of each and every one of your pages and post.

PadPressed
PadPressed is a great plugin to make your blog act like a native app in iPad. It works with your existing theme and features accelerometer and touch navigation support as well as custom home icon and built it social sharing.

OIO Publisher
OIOpublisher is a powerful ad manager that focuses on maximizing your revenue, saving you time, and keeping you in complete control of your ad space. It features fully automated sales, no middleman commission, option to run 3rd party ad networks alongside your own ads.

WPtap
WPtap is a premium WordPress plugin that can instantly convert your WordPress site into web-application experience when viewed from iPhone, iPod Touch, touch-based Blackberry, and Android smartphones.

aMember
aMember Pro is a powerful membership and subscription WordPress premium plugin for selling digital subscriptions and downloads. It features support of multiple payment systems and allows you to setup paid-membership areas on your site.

Scribe
Scribe is a premium SEO plugin for WordPress. It analyzes your content and tells you how to gently tweak it to get most traffic from Google based on 15 SEO best practices. Scribe also helps you build back links.

Events Calendar Pro
Events Calendar Premium plugin for WordPress enables you to rapidly create and manage events using the post editor. Features include Google Maps integration as well as default templates such as a calendar grid and event list.

WP PDF Stamper
WP PDF Stamper plugin allows you to dynamically stamp a PDF file with the customer’s details (e.g. name, email, address etc.) upon purchase. Additionally you can password protect the stamped PDF files to prevent users from being able to copy, modify or print the content of the file.