Parse had some initial success among native game designers. If you were writing an iOS or Android app and you weren't quite sure how to code OAuth or Push Notifications, then Parse was an easy fix for the problem. They also provided help with User Management and a place to store the information on your High Scores Screen.
Unfortunately this audience didn't have much money, and Parse didn't have the features that an enterprise customer would need, and so Facebook decided to shut the company down and "open source" what was left. Better late than never I suppose, DreamFactory was Apache License from day one. At any rate, I've had a few people ask me about the differences between Parse Server and DreamFactory, so we whipped up these comparison tables.
|Active Directory Support||✓|
|Call External Services||✓||✓|
|Web Based Admin Console||✓|
|Role Based Access Control||✓||✓|
|Push Notification Support||✓|
|Server Side Scripting||✓|
|Building Custom Services||✓|
|SOAP and REST Translation||✓|
|Combining Multiple Databases||✓|
|SDK / Sample Apps||✓||✓|
|API Management *||✓|
|API Analytics *||✓|
|Multi-tennant Hosting *||✓|
|Data Sources||Parse Server||DreamFactory|
|File Storage Support|
|OpenStack Object Store||✓|
|Rackspace Cloud Files||✓|
There are some big differences hidden by single lines in the tables above. The new Parse Server doesn't have a web based administration console. This will make it very hard to configure. There is no interactive documentation, but I guess that is OK because they don't have that many services, either. They only support one backend data source, with zero support for SQL, which we consider to be the primary enterprise use case. They don't have support for server side scripting or custom services, another major gap.
So taken all together, you can see why Facebook gave up on this. The SaaS model didn't work for enterprise customers, and the product was falling farther behind every year. You would be better off starting from scratch. Or, better yet, install the world's best REST API Platform today and spend your time building a real application on an enterprise-ready stack.