What's the alternative though? A smartphone is a device you can pretty much guarantee people will keep with themselves and in good working order.

It's less of a failure point then any bespoke interface device and more durable.

But when it fails, everything fails at the same time.

It's not that far fetched that if your phone dies, you can't unlock your car, you can't pay for the bus, your insulin pump now lost its controller and you can't call anyone.

> A smartphone is a device you can pretty much guarantee people will keep with themselves

It's a device that many will keep, some might not, some will forget it, and seeing the state of some phones, you can't assume that it will be in good working order. Many apps will also require a relatively new phone, what if you can't afford a new phone?

The traditional finger stick readers are still very available though right? I see them still at pharmacies.

True, but that tech is bad.

My current GCM uses NFC and my phone to connect with my pump. I would like to remove my phone from the loop. Just use the pump to connect to the sensor directly.