This is how I set up my unlocked iPhone 5 to get data and mms to work with Straight Talk
This worked for my unlocked iPhone 5 with iOS 6.1.4.
You may have to try the T-Mobile sim swap method here
to get to Cellular Data Network inside of settings.
*Sorry, the video cut off before I could show the MMS on John Doe's phone, but you can see it was sent on my unlocked iPhone 5.
I used the following:
*I didn't have to do anything to get data and text working on my unlocked iPhone 5, it worked as soon as I activated my sim and $45 plan card. MMS was different and I used a mix of the proposed settings on the Straight Talk plan card along with other suggested settings for the iPhone 4, 4s shown on many sites including here on youtube. I have an unlocked iPhone 5, so you may only be able to get to Cellular Data if you use the sim swap method if your iPhone is not unlocked.
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