The linking word “although” (underlined in two sentences of the text) establishes a contrast between ideas, and it may be…

The digital divide is very narrow, but it is clearly widening.

The digital divide is seen in low and middle-income countries, but it is not present in high-income countries.

Today there remains a digital divide, but only 51% of the world’s population has access to the mobile internet.

There is free access to mobile communications in low and middle-income countries, but not in high-income countries.

Today there remains a digital divide, but the social divide in 51% of the world’s population is narrowing.

The lack of access to mobile communications is inexistent in low and middle-income countries, but it affects high-income countries. 

The digital divide is narrowing, but it is still very wide.

The digital divide is found in low and middle - income countries, but it is also present in high-income countries.