Helium network has been growing fast. Just crossed 20,000 hotspots and will probably reach 100,000 this year. It uses a crypto mining incentive so the network expands without any central corporation needing to spend a dime on infrastructure. People are already building cool IoT projects with it from adafruit kits.
This would be far better if the currency was used to pay for connectivity, and the router was reimbursed for routing.
Connectivity has a cost, and none of these networks will amount to anything unless the model can incentivize all aspects of the infrastructure necessary
https://explorer.helium.com/coverage