does it have any GUI instead of command line nrfjprog?

[Mikhail]

I search some GUI for win where I can flash mass devices. With lock flash and flash merge hex or separate hex's.

[endnode]

That's nRFgo Studio (no, it cannot merge HEX files but it doesn't need to as it is flashing each one separately). Btw. command line oriented solutions are the usual solution for mass production at CM, alternatively they build their custom simple UIs with features oriented to the jig itself not so much to SWD flashing itself (for that they typically call J-Flash or SEGGER DLLs and that's what nRFgo Studio does as well).

[Mikhail]

thanks for answer