Mobile data settings
1. Go to Settings → Cellular → Cellular data options → Reset Settings. Restart your phone.
2. Before you edit the settings please turn off the Wifi:
Swipe to turn of Wifi at Settings → Wifi
3. Go to Settings → Cellular
4. Enable Cellular data og Data roaming.
5. Go to på Cellular data and add the following:
Cellular data settings
6. Restart your mobile phone to apply the new settings. You are now reayd to use Cellular data.
Your iPhone is autmoatically set up with MMS with iOS 8 installed, but remember that MMS must be enabled at Settings → Messages.
To receive new settings:
Go to Settings → General → About