I'll answer to you nadia since I think that my project is an enabler to the problem you raised though I think that my answer is a bit too technical and off-topic to the issue we're discussing.
Infrastructure for Africa is costly because much of hardware and services must be paid in $ or € and imported (customs fees not included...). On addition of this, there is some costs related to hosting software.
An alternative could be an african cloud infrastructure ISO to the top notch Silicon Valley ones... I know a guy here in Tunisia who's developping an opensource alternative and compatible to Amazon S3 called minio. Another bunch of hackers set up a metaplatform with all tools included for free called http://op.tn/ That's an example...
And a french NGO called framasoft is setting up a lot of free and open services online https://degooglisons-internet.org/liste
If we got a strong community of hackers with spare time, they could initiate alternatives. However I'll say that most of software for infrastructure is available opensources and the real difficulty is about hardware and skilled people.
Moreover I'm aware of a tunisian governement project to set up a national cloud to mutualize investments. I think that many other countries in Africa are trying to do the same. These type of projects are HARDLY doable in p2p citizen-centric form and mostly needs heavy investments :s
(Btw Nigeria, Tunisia, Morocco, South Africa, Egypt and especially Mauritius are quite strong in IT.)