HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.

Floobits - Floobits brings real-time collaborative editing to text editors, IDEs, and now Atom.

HackerEarth - HackerEarth is the network of top developers across the world. They connect to start-ups, tech companies, organizations and discover the best developer jobs. They participate in programming challenges and compete against other top developers.

codebunk - Realtime Collaborative Editor with Code Execution, REPLs and Chat

Coding View - Coding View is live collaborative coding environmentdesigned for technical phone interviews. It features web version of Visual Studio Code, as well as access to real terminal. It has a built-in compiler for most popular programming languages.

coderpad - Collaborative code editor with in-browser, real-time execution. Conduct programming phone screens like a boss.