Maybe you could elaborate on what you mean by "express ble"?
However, the nRF52840 is supported by Zephyr and you find find various samples in the nRF Connect SDK. I suggest you take a look at the nRF52840 documentation. We also have the nRF52840 development kit, which is a hardware development platform used to design and develop application firmware on the nRF52840. The nRF52840 DK have a SEGGER J-Link OB Debugger with debug functionality.
