GUID as a primary key..
allow the use of an auto generated GUID ID instead of only int..
Jason R. Craig commented
Partially connected applications need to be supported in Visual Studio!
Microsoft killed the sync framework in 2010 and has left developers with zero tooling to make local database cache apps.
The SQL azure data sync has been in CTP for over 3 years and that looks like it was abandoned too.
I tried to make a custom odata solution in light switch but they did not support guid pk's.
I am disappointed Microsoft did not address this in all this time, please let the developers decide whats best for them rather than you deciding for us