I am using my iPhone 4 in Colombia with an altered sim card. The guy cut a sim card down and filed it into a micro sim. It works perfectly. I am on Tigo. The same thing should work for the Ipad. Same technology. I will admit the 3g seems very slow. The cost of the filed sim card about is $5.00 U.S.
IP
Ipad or Ipad WIFI can access WiFi network ( like Ipod touch) where as IPad 3g has SIM card slot and can access internet where WiFi networks are not available ( you require Data Plan from AT&T in US) for Ipad 3G if you want to access internet where WiFi network is not available. What happens if you cancel the monthly payment on the Ipad 3g, does it still work?
It will still work, you just wont be able to use 3G.
Only if you want to use it on your 3G iPad.
No it is different ipad has micro sim iphone does not and you have to activate it on the one you bought it with.
Wi Fi and 3G
Yes it is just like a phone. :)
If you do purchase an iPad with 3G, you will not need home wireless internet. But you can also connect to a home wireless internet with an iPad with 3G. You will need to pay monthly for the AT&T 3G fees.
No.
All New iPads (they're NOT called the iPad 3) are sold as a 4G LTE or Wi-Fi model. The 4G model will automatically work with 3G networks. You will need a SIM card from your local mobile phone provider, and will have to sign up for a data plan. If you don't have a 4G LTE iPad, you have a Wi-Fi model, and that won't work with 3G, unless you tether it to your phone.
The iPad accesses the web via its Wi-Fi or 3G connection (if you have a 3G model).
I don't think we will see it for the present iPad, as it requires a GPS system as well as a 3G Internet connection to work well wherever you are.these are only present in the 3G versions of the iPad. Siri is still officially a beta program, so expect the next iPad might have it...
In the related links you'll find a picture of an iPad with two things circled; the 3G sensor at the top and the number of GB. If your iPad has a 3G sensor then it is a WiFi + 3G iPad and if it doesn't then it's just a WiFi iPad. Also it shows the number of GB.