I've used Cloud9, Nitrous, and currently messing around with Codenvy, and a few others that were very lacking. My favorite so far is Cloud9, which has a ton of

I've used Cloud9, Nitrous, and currently messing around with Codenvy, and a few others that were very lacking. My favorite so far is Cloud9, which has a ton of useful features. Nitrous is second but lacking features such as code beautify which is annoying.