The fact a program like this would be so cheap means that it should be possible to apply at large scale. The highly mobile nature of the hardware also means that as more people have computers and phones of their own in cities, these mobile cafes can spread to more remote regions. -Possibly on bikes with satellite connections.

Financially, a single operation/cafe's expenses would entail: 
-Used smart phones (for 6 people $60) 
-Wifi router and modem ($50-100)
-Internet service/provider
-Cost of staff or volunteer.

It's important to remember that small numbers of staff can be used to organize large numbers of volunteers. And that in some areas there's already local leadership or communities that are willing to facilitate and maintain programs on their own as well.

It's also critical to remember that each phone can serve numerous people, but if we're serious about increasing literacy they're each going to need a lot of time with them.

It may also be possible to focus more on the youth and the others who express interest, rather than trying to "educate" the general public. Afterschool programs would help the youth learn while potentially helping parents with childcare. Meanwhile volunteers running the organization get more than just the satisfaction of helping the kids and their nation, they'll get to tech and management experience for their resumes, free internet access of their own (in shifts or something), and they'll get to be at the center of future collaborations. Grandparents love spoiling kids and Needpedia makes it easy for them to see these independent projects, so there could be robotics and all kinds of other cool things at these after-school clubs.