What the APN settings mean
Android's APN configurations contain information vital for using internet data while you are on a cellular (mobile) network, as opposed to Wi-Fi.
In most cases, you should not have to change these as your phone will automatically choose settings appropriate for your carrier. In some cases, you will need to input some information provided to you by your carrier.
The most important fields for your APN configurations are APN and APN type. APN must match the value your carrier requires for this type of connection. APN type must describe which type of communication should use this APN configuration, such as "*" if all communications can use the same configuration, "default" to specify general internet data (but not MMS), and "mms" for MMS messaging. For MMS messaging to work, you'll also need information in other fields.
A user-chosen name to apply to this APN configuration. Has no effect on the connection.
Determines which Access Point Name your device should quote when communicating with your character. It must match a valid value for that carrier.
An optional field allowing you to specify the address of a HTTP proxy to use for all web traffic over this connection.
The port number to use when communicating with the proxy listed in the above (Proxy) field.
In rare cases your carrier may require a username and password in order to access data. Usually left blank.
WAP Gateway Server, a feature not usually used in modern smartphones and devices.
Details of the Multimedia Messaging Service Center to use for sending and receiving of MMS messages.
HTTP proxy details to be used only for communicating with the MMSC to send and receive MMS messages.
Specifies the protocol that your device should use for sending and receiving MMS messages. Usually does not need to be modified.
Mobile Country Code and Mobile Network Code, which together identify the particular carrier you will use.
Method used to supply your name and password to the server for your data connection. Usually not used.
Important field specifying which types of data connection your device should use this APN configuration for.
For devices that support IPv6 networks, this specifies whether to enable IPv4, IPv6 or both.
When having multiple general purpose APN configurations, allows you to choose which one is currently enabled.
An optional field allowing you to specify which communication technologies may use this APN configuration.
Fields allowing you to restrict use of this APN to certain MVNOs (mobile network resellers) or subscriber accounts.