Apple iOS APN Locations:
If your carrier allows you to view the APN settings, you can find it on your device under these menus, according to Apple's support document:
- iPhone: Settings > General > Network > Cellular Data Network
- iPad: Settings > Cellular Data > APN Settings
Android APN Location:
Go to Settings > Wireless & Network > Mobile Networks > Access Point Names
Android and iOS APN Settings:
Another resource for both iOS and Android devices is the APNchangeR project, where you can find cellular carrier settings or prepaid data info by country and operator.
*If these steps didn't restore your data, please follow these steps.
1. Remove SIM
2. Delete all APN's
3. Power off and do NOT insert SIM (leave off for 20 minutes)
4. Power on WITHOUT SIM
5. POWER OFF
6. Reinsert SIM power on.
This will force a PRL update and should install the APN automatically
*Note: rooted phones may have an issue with editing the APN