For those needing to use payg in the USA - Useful Info

mrcamp

Thought I should post this here, since the question comes up quite often about using a phone in US for voice and data. You basically just need an unlocked phone with the US frequencies, which they all do these days.

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"Last month I was in the US for 1 week and used 98mb of data which had I been roaming would have cost me $1000 – I got it for $15 on my iPhone.
Additionally all my incoming calls only cost me 20c even when someone called my UK cell number and not $2.00 per min. My outgoing calls to the UK were 39c and not $2.50. Even cheaper for incoming if my colleagues in the UK called my US cell number – and as calling from a landline in the UK can be cheaper when calling a US number than a UK mobile they saved money too!

To make this happen you need an AT&T SIM card, a gophone account (PAYG from AT&T), callingmart account for cheap calling credits for the gophone account and a Skype account with Skype in/out enabled. Lastly and most important your iPhone should be unlocked for use on any network. Mine is on O2 in the UK and the network do this free of charge through a simple request form on the web.

You need an AT&T SIM for 3G to work as T-Mobile the other GSM provider in the US only has EDGE compatibility for the iPhone. This is due to the frequencies that an iPhone works on and although T-Mobile offers 3G (or even 4G) it won’t work on an iPhone.

Firstly on arrival in the US go to Wal-Mart or Best Buy and buy the cheapest gophone. When I was in the US recently there were clearance bins with phones for $2.99. Do not buy any calling credit as we can buy that later and with some discount from callingmart.

If it’s an iPhone 4 or 4S you have, then you need a micro SIM. For all other iPhones a standard SIM is all that is needed. The gophone starter pack comes with a standard SIM however this can be converted to a Micro SIM no problem.

If you need a Micro SIM, then before you go buy a cutter from eBay or amazon. However do not cut your SIM until you have activated it in the gophone.

Activate the phone on line (instructions are in the box) and choose a smartphone tariff. Add your calling credit – I use callingmart (.com) where I get a 5% discount off the prepaid rates. The smartphone tariff is $2.00 per day and is only charged on days you make or receive a call or text message. I initially got a $100 voucher as it gave me 12 months connectivity. I still have credit on my account.

Use the IMEI from the gophone phone. You can keep this phone, give it away or as I did recycle it for charity. Register to manage your account at paygonline.com. This is a better site than the automatic linked site when initially setting up your account.

I used my hotel address to register the phone as AT&T does not verify your address.

It is important to add a data package - best value is 500mb for $25 valid for 30 days but you can also buy 100mb for $15 or 10mb for $5.
Now your SIM is active you can cut it down and pop it into your iPhone.

To get data working you need to change the APN to AT&T settings. This can be done manually or with a Wi-Fi connection open safari on your iPhone and go to www.unlockit.co.nz and follow the instructions. Disable or uninstall any data shrinking apps such as onavo before you do the configuration. You can always reinstall when back home.

You can now make and receive calls and use data and because you chose the AT&T smartphone tariff it allows data at 3G speeds."

http://www.flyertalk.com/forum/travel-technology/1329119-using-t-payg-sim-unlocked-iphone.html