Maintaining a good Bluetooth 4.0 connection between the RFLKT and your phone is critical to keeping the data flowing properly. The biggest problem with connection issues is that the human body is primarily water and water is a perfect insulator to 2.4GHz radio traffic.
If your phone is flat against your back in a center jersey pocket it is very difficult for the signals to make it to the RFLKT. If you place your phone in a side pocket with some space between your phone and skin the signals can find their way to the RFLKT much more reliably. Unless the phone is in direct line of sight with the RFLKT, the signals will have to bounce off surrounding objects like the ground or nearby trees.
As a last resort, placing your phone under the saddle in a saddle bag will provide a line of sight to the RFLKT and subsequently a much much better connection.