Freemium
WordPress SEO by Yoast
Access tools that increase your presence in search engines. Edit titles, generate XML sitemaps and edit .htaccess and robots.txt files.
Paid Plugin
Gravity Forms
Create new forms with a drag and drop interface, add them to your post editor with a shortcode or template files, set up admin notifications, and customize every step of the way.
Freemium
WP Migrate DB Pro
WP Migrate DB sync up local and production MySQL databases with one-click. It provides automatic search and replace, transfers over HTTP/HTTPS and easy push, pulls functionality using built-in API key.
Freemium
Advanced Custom Fields
Make custom fields in WordPress easy and quick. You'll get set-up with a GUI for adding new fields, and functions to incorporate them into your themes.