Which J-Links work with the Nordic-based Bluetooth modules? For example, BL65x, BL5340?

All Ezurio Nordic-based Bluetooth modules, which include the BL65x series and BL5340 modules, can be flashed with any SEGGER J-Link device which supports working with Cortex-M based devices. Here is a sample list of J-Links which will work with the Nordic based modules as of the time this FAQ was written:

SEGGER J-Link Probes and Flashers for Nordic based products: 

J-Link PRO 
J-Link ULTRA+ 
J-Link PLUS 
J-Link BASE 
J-Link EDU (Student Only Use)
J-Link for Cortex-M 
Flasher PRO
Flasher ARM 
Flasher Portable

*Note: All Ezurio Bluetooth IoT products based on Nordic's nRF52 series can also be programed with these J-Link devices, such as the BT510, BT610 and the MG100.