I will be building an in-house, Occasionally Connected App (OCA). What technologies would you suggest I employ.
Here are my parameters:
You could create this stuff from the ground up, it seems.
However, this seems an awful lot like a CRM application, and it wouldn't surprise me if you could find an enterprise software package to do this without starting from scratch and instead modify one of the configurations to meet your business rules.
In a previous life, I was a configuration developer for this thing called Siebel that might be close to what your'e looking for. They even have a built-in synchronization tool called Siebel Remote.
It might be a cheaper route to go than rolling your own from scratch.