Loon, a California-based unit of Alphabet, and Telkom Kenya debuted 4G Internet service in central and western Kenya, a 31,000-square-mile area that includes the capital Nairobi. In preparation, over the last few months Loon launched 35 balloons 12 miles into the sky, above commercial airplanes. Previously, Loon provided Internet service via balloons in Puerto Rico after Hurricane Maria destroyed all the cell towers in 2017. Telecom executives are watching to see if Loon’s technology is reliable and profitable.

The New York Times reports that, although Kenya already has great Internet connectivity, with about 39 million people out of a total of 48 million already online, Loon chose it because of “its openness to adopting new technologies.” Loon chief executive Alastair Westgarth, who dubbed Kenya “an ideal place for us to begin this new era of stratospheric communications,” reported that, “the country has been incredibly innovative about finding new ways to connect unconnected populations.”

The balloons are “the size of tennis courts,” made from “sheets of polyethylene … [and] powered by solar panels and controlled by software on the ground.” The balloons, which transmit Internet signals to ground stations and personal devices, “last for well over 100 days in the stratosphere before being returned to earth.”

In Africa, only 28 percent of the 1.3 billion people are Internet-connected, and Loon’s solution is “intended to offer countries a cheaper option than laying cables or building cell towers” — and enable them to make Internet costs affordable for more Africans.

In the test period in Kenya, “over 35,000 users on the Telkom network connected to the Internet through a Loon balloon … [and] the users, some in remote towns in Kenya, used the service to stream video, browse websites and make video and voice calls on applications like WhatsApp.” Loon executives, however, “would not reveal the costs of the Telkom contract or any financial arrangements.”

Loon isn’t the first to attempt to bring Internet to Africa. Facebook backed an effort to do so via drones, but “abandoned the venture after several setbacks.” The project has its critics, some of whom say that, “Loon and Telkom are launching the service in parts of the country where cellular networks have already been expanded, instead of targeting underserved regions like north or northeastern Kenya.”

Others note that, “many people in poor or remote areas cannot afford phones that are compatible with the 4G service Loon provides.” “I feel this solution is inordinate with the problem being solved,” said Node Africa chief executive Phares Kariuki. “Loon is a fringe solution for places where last-mile connectivity will be too expensive because the people are sparsely populated. It’s not the best solution for this market.”