From hacker spaces to full-fledged ICT business incubators offering office space for start-ups, Africa’s inventory of tech hubs is growing almost by the week, World Bank reports.

Unlike African mining and agriculture, where wealth is extracted and knowledge imported, the African digital revolution is home grown.

The continent’s 700 million mobile subscribers use services that are provided locally to solve local problems, and they’re downloading apps developed locally.

Tech hubs are one of the main sources of locally developed apps. World Bank worked with the Botswana Innovation Hub, iHub in Kenya and BongoHive in Zambia, to create a map of tech hubs.

As of September, the continent has 117 tech hubs, up from 90 a year-and-a-half ago. Twelve countries in Africa account for 93 of them. That means about 80 percent of all African tech hubs can be found in just 12 countries.

Of the tech hubs formally recognized by World Bank, the majority — 79 — are led by citizens. Ten are led by governments, nine by universities and 19 are hybrids, made up of a combination of the three.

Tech hubs come and go, World Bank reports. There’s a high failure rate — an inevitable consequence of innovation and testing ideas. On the other hand, iHub in Kenya with 13,000-plus members lists more than 150 companies that can trace their origins to ideas incubated there.

Governments like getting involved in funding tech hubs, partly because of the potential for job creation, especially for youth, and partly because hubs could harbor the next MPesa, World Bank reports.

Ditto for investors, financiers and funding institutions. Botswana Innovation Hub is an example of a government-driven initiative that’s transitioning to a more sustainable model with assistance from the World Bank.

Check out African tech hubs at a glance plus the 12 top countries in Africa for innovation hubs.

Sources: World Bank, Crowdmap