I am working in a similar situation and am a little bit confused on what hardware kit or tools I need to buy. I already bought the nRF51 Bluetooth Smart kit, but don't think it is what I wanted.
I am trying to code the firmware for the MetaWear device (https://www.mbientlab.com). I already have the Conn 10 point connector soldered to the board, just unsure of what eval/dev kit or alternative solution I need to buy. I thought that maybe I just needed to get a J-Link LITE Cortex 9, but learned you can only get that with a kit. Also, wasn't sure what IDE or SDK I needed to make this possible.
I am a bit lost as you can tell...can you help clear some of this up? I really appreciate it!