[General Questions and Answers] Toniolli:
well here is what i belive the difference's are GSM and CDMA are just different types of cell phone technology used.

Differences:

GSM is used by att and tmobile and what you are thinking of getting straight talk and that means that they use a SIM cars, which is that little chip that gets inserted behind the battery. GSM also is used worldwide so it lets you use the line (Roaming) anywhere you go in the world.

CDMA: does not use a SIM card (chip). this is most widely used by verizon and is not compatible in other countries. But now they have phone like the iphone 4s at verizon that uses both GSM and CDMA so people can use it here and also outside of the country.

as a consumer that is the difference you need to know.

3g and 4g: is simply the name given to the network that a cellphone company has that determines the speed. for example, 4g is just simply faster than 3g because it has a bigger capacity, which makes it faster. The g stands for generation so 3g is third generation and 4g is fourth generation as technology advances and network capacities increase they will advance in the future to the 5fifth generation and so forth.

Wi-Fi

Connecting to your Personal Hotspot via Wi-Fi is the default option provided by Apple, since you have to specifically accept if you also want to enable the Bluetooth connection. A Wi-Fi connection provides:

Pros

High throughput: Throughput via Wi-Fi Personal Hotspot can be of around 30 Mbps between two devices and even more.

Faster: Connecting via Wi-Fi tends to be quite faster than connecting via Bluetooth.

Cons

Might need you to reconnect every time: Wi-Fi tends to be unstable and to turn itself off every time you put your iPhone to sleep. This means that you have to take out your iPhone and re-enable the Personal Hotspot if you want to connect.

Time limit: Perhaps the biggest drawback of using a Wi-Fi Personal Hotspot with your iPhone is that in order to minimize power consumption, your iPhone only gives you a short while (90 seconds reportedly) to connect a device to it after you enable Wi-Fi Personal Hotspot. If you take longer than that, you are forced to enable the option again.

More power consumption: The Wi-Fi Personal Hotspot consumes more power than its Bluetooth counterpart, which is also part of the reason it only gives you a short while to connect a device.

A bit more complex: The iPhone’s Wi-Fi Personal Hotspot requires you to enter a password and to configure your own security options.

Bluetooth

Contrary to the Wi-Fi connection, using your Personal Hotspot via Bluetooth offers some key advantages and one huge drawback:

Pros

No time limit: Once you enable Bluetooth Personal Hotspot, there is no time limit for you to connect your device to your iPhone.

Automatic pairing: Bluetooth remains dormant and ready to connect to your devices the moment you wake them up. Additionally, Bluetooth is more power-efficient than Wi-Fi.

Security handled automatically: The security level of a Bluetooth Personal Hotspot is equivalent to Wi-Fi’s WPA2, and it is all handled transparently from the moment you connect to it.

Cons

Very limited throughput: Without a doubt the biggest drawback of using a Bluetooth Personal Hotspot is its limited throughput, which can be of just 3 Mbps at the most, making it 10 times less than what your Wi-Fi Personal Hotspot can i personly would try all 3 because there is a usb option as well find what is best suited for your service your location ect. then you will have your perfect transfer also i think tmobile would be your best option for were your living ok lets see my lady works for sprint and i tried out there mobile hotspot when 4g first came out and i was able to run black ops on my ps3 and play online but it was pretty laggy but not to bad so basically what i am saying is i think it was just regular 2g or 3g back then and it was able to run my monster ps3 so straight talk gsn are cdma should be fine hope this was helpful