How to Setup Straight Talk Data on Nokia Lumia 610,710,800 & 900
On Nokia Lumia devices (Lumia 610, 710, 800 & 900) you can use the Network Setup app to get your Straight Talk data going. Download and install the app by searching "network setup" in the app market. You will need this to browse the internet, use the app market, setup email and for any app that uses the internet. You can setup the data along with MMS from the same screen. If you've set up your data from the standard windows "Cellular" menu, then you probably want to delete the apn from there to minimize any conflicts. Here is how to do it.
1. From the Home screen, tap the upper right hand arrow to go to the Main Menu.
2. Locate the Network Setup app and tap it.
3. Once the app launches, it will perform a brief set up so wait for that to finish. When it does, simply tap the + icon to create a new APN.
4. Enter a connection name in the first box.
5. Tap the "Make this My Current APN" box to.
6. Enter att.mvno in the "Access Point name" box. This is the only box that's needed for data. Tap the Disk icon to save or proceed to the MMS section to enter the MMS apn. Visit the MMS Setup page for MMS instructions.
If for some reason you find that this does not work, then simply clear the att.mvno entry from the Internet Apn section and use the standard Windows 7 Cellular screen to create your data APN. That's all there is to it!