Why does Mac disconnect from my phone?
Disable App Nap, one new feature from OSX 10.9
App Nap automatically reduces system resources to certain applications that are not currently in use. It’s one of several changes in Mavericks that helps increase Mac battery life, but it also has the potential to interfere with some apps and user workflows.
Since the iPin Host shrinks down to the background while connected with iPhone, it is then considered by Mavericks to be "not currently in use". Therefore, the reduced system resources will cause the remote function to be delayed or even easily disconnected from the iPhone.
So, please follow the simple steps to disable App Nap to keep your iPin Host work properly.