There is a lot of variance in the distribution of phone capability. There is nothing scientific in my survey, just stuff I picked up. Most people have very basic phones about on par with: http://www.gsmarena.com/nokia_1202-2573.php
There are also a lot of feature phones that might have been normal in Europe around 2003-2005.
But there are also a large number of people (millions) who have smartphones. The dominant platform is the blackberry.
Mostly regular phones (nokia 1200s are ubiquitous) but especially in places like Kenya, smartphone penetration is beginning to increase quickly. SMS and USSD are generally most useful. WAP can be used, but penetration of WAP enabled phones is much lower. One thing that works at times when a WAP interface is required is to follow some sort of "kiosk" model where someone who has a WAP-enabled phone provides services for others without.
There are also a lot of feature phones that might have been normal in Europe around 2003-2005.
But there are also a large number of people (millions) who have smartphones. The dominant platform is the blackberry.