I do not believe you are comparing apples to apples here. The R1 and R2 are are MGIS products (I realize the R2 can also be used by Trimble Access) and the use of 3rd party software is more likely, whereas the R3 (L1 only), R4 all the way to the R10 are survey receivers. The survey receivers typically require a specialized software, like Trimble Access to configure and utilize. Once configured you could send the NMEA data to a 3rd party device if that device supports the bluetooth connection or a cabled connection.
Trimble may have some sort of SDK for their survey GNSS receivers, but it is doubtful.
I would recommend contacting a local Trimble dealer or Trimble themself. We did the same with Leica when we wanted more information on the Android version of their Zeno 20 device. It was easy to navigate their channels and even easier to work with on the questions we had.