This is a pretty broad question, but I'm curious to hear how people would go about this and what parts they would use to do the heavy lifting.
Imagine you had a bluetooth module, it works fine and can be reprogrammed to act as a central device without too much fuss. You want to bridge data from your bluetooth peripheral devices to a wifi network. How would you go about this? would you pick a wifi MCU like a TI CC3200 or Freescale (NXP) KW series and just connect it directly to the bluetooth module? Or would you want an intermediate microcontroller like a PIC32 to do some of the heavy lifting and have a separate module for the WiFi too? What would your reason for either be?
Edit: To be more transparent, I've noticed a few IoT systems which have a bluetooth-wifi bridge component, which usually have a wifi and bluetooth module, then an additional microcontroller in between. WunderBar is a good example of this. Why would you bother with an additional microcontroller if you were using something as capable as a CC3200?