These low cost phones, once they can be fully supported on US networks, will alter the telcos business model, in my opinion. There will be no reason to entangle phones with service. No need for brick and mortar Sprint, Verizon, etc, phone stores all over the place. The big carriers will have to compete purely on service offerings, coverage, reliability and price. This will make the market far more transparent to the end consumer and we'll see a much more rapid slew of both hardware and software innovations.
The giant telcos will be forced to look high and low for ways to distinguish themselves other than backdoor deals with the manufacturers. Since they own the cloud, I expect the big innovation will come in the way of AI offerings, most likely in conjunction with major industry verticals. Example will be JVs with major travel companies like Kayak or Expedia which will offer far easier ways (using expert systems and big data) to book travel for individuals and groups.