The feature that stands above the rest is their customer service. They have set the bar. Responses to issues are immediate and often come from the founder himself. Extraordinary! Then you add the robust feature set and ease of use, and you have a first-class platform.

Graphical 'language'. Excellent backend support: DB, file system, cloud coding. Very good online support. The feel of a company/system evolving in the right way.

Easy use of databases for non-programmers