The number of mobile subscribers in Sub-Saharan Africa will increase by 190 million by 2025.

This is according to the latest GSMA Mobile Economy report officially unveiled at the GSMA Mobile 360 Africa event being held this week in Kigali.

The report says there will be 634 million unique mobile subscribers across the region by 2025, 52% of the population, up from 444 million (44%) at the end of 2017.

Moreover, the contribution of the mobile ecosystem to the region's GDP is expected to rise to over US$150 billion by 2022, representing about 8% of Sub-Saharan Africa's GDP.

GSMA research suggests however that affordability and the region's population of mostly youth is impacting subscriber growth.

This is problematic say experts, particularly because the region's mobile penetration rate of 44% is well below the global average of 66%.

Referencing data from the World Bank, the report added that while about 40% of Sub-Saharan Africa's population is under the age of 16, the demographic segment has significantly lower levels of mobile ownership than the population as a whole.

Despite the slow growth, more people are investing in smartphones because of the lower device costs, according to the report.

"Lower device costs is serving to accelerate migration to 3G/4G mobile broadband networks and services," read an excerpt from the research.

The prediction is that mobile broadband will account for 87% of mobile connections in Sub-Saharan Africa by 2025, up from 38% in 2017, and that almost 300 million new subscribers will use their devices to access mobile internet services over the next 7 years.

John Giusti, Chief Regulatory Officer at the GSMA said, "More needs to be done to extend connectivity to the remaining unconnected and underserved populations across Sub-Sahara Africa, but this will require a focus on long-term industry sustainability that can only be achieved through investment-friendly policies and supportive regulatory frameworks."