[jon-wood]

The article is estimating the price of one of these things as being $5 - I imagine that at least for an initial trial Amazon have decided they can make a decent return on them at that cost without certifying their own components.

[BillinghamJ]

Also a key factor may have been the time required to get their own stuff certified vs using off the shelf stuff.

[joezydeco]

A lot of people prototyping in the IoT space are using the precertified modules.

There's not much more to it: the transmitter is already soldered to a small piece of PCB but has the antenna and necessary tuned discretes on there and ready to go. Doesn't add much to the cost: like BillinghamJ says it's the certification time and cost that's not really worth the trouble if you can just amortize it into the cost of the module.

[minthd]

The cost comes from adding another company to the process - the module maker.

But sure, at this stage it might not be worth it , maybe later.

[joezydeco]

Hardly a concern anymore. These are just line items on a bill of materials now:

http://www.digikey.com/product-detail/en/450-0103C/450-0103C...

[minthd]

$7.8 is pretty expensive when you can get a bluetooth mcu(in volume, from dialog i think) for $1.

[joezydeco]

Like we said earlier, you can choose between a raw chip (like the Dialog) and handle the antenna design and all the various governmental certifications and testing yourself ($$$)..or you can buy a precertified module that drops in and you're ready to go.

It depends what you can afford and what each path will save you in the long run.