Internet cafés are common throughout Kenya and usually offer decent connection quality. Expect prices around 0.50c/1KSh per minute. Most internet cafés now charge 0.50c KES per minute.
Safaricom, Airtel, Orange Telkom and YU: After buying a starter SIM card, you can go online immediately if you have an internet-capable mobile phone or modem. If you use your account credit for access, however, the prices are steep. It’s much cheaper to buy a data package, and the more expensive ones offer a much better price/limit ratio. For example, in January 2016, a 2GB data package costs KES 1000.00 from Orange Telkom, while a 3GB from Safaricom costs 1000.00. A SIM card costs between KES 50-100.
You will need to show valid identification as it is a legal requirement that all SIM cards must be registered.
You can purchase the packages by topping up your account with scratch cards and then dialling *100# or *544# (Safaricom and Airtel), *124# (Orange Telkom). Be warned: once the data package is used up, internet access is via a fallback method using your current account balance, which is much more expensive.