jQuery - The Write Less, Do More, JavaScript Library.
Sortd - Rated the #1 App for Gmail
Modernizr - Modernizr is a JavaScript library which is designed to detect HTML5 and CSS3 features in various browsers.
KanbanMail - A Kanban board for your emails.
React Native - A framework for building native apps with React
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.