Airtel Internet settings for Nigeria

In order to be able to browse the web with an Airtel sim, you need to have it configured with the valid settings for the network. 
In Nigeria, Airtel offers internet browsing both for mobile and desktop.
Once you have a capable device that can act a a modem and an Airtel sim subscribed to a data plan, the next thing you need it to setup the internet settings to be able to access the internet.
Here are the internet settings for Airtel in Nigeria:

Internet Settings for full browsing
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APN (Access Point Name) : internet.ng.airtel.com
Username : internet
Password : internet

Internet Settings for mobile browsing:
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APN (Access Point Name) : wap.ng.airtel.com

Username : wap
Password : wap
Homepage: http://wap.ng.airtel.com or any site you want
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If you have all of these configured for your device, you can start browsing the web immediately or subscribe to any of their data plan that suits your budget or taste.