What’s the advantage an unlocked over a locked tablet?
A locked tablet has to be used with whichever carrier you purchased the tablet from. In the case of the tablets here, they were originally locked to AT&T so before they were unlocked you could only use them with an AT&T mobile plan (they still work on wifi without a plan).
An unlocked tablet can be used on any GSM carrier. So instead of only being able to use AT&T, you can use any of the carriers below. Many of these likely have better service and/or pricing in your area. In addition, if you travel overseas, you can buy a cheap SIM card and have inexpensive data there instead of the insane roaming charges that a US carrier would charge.
Asset/Vada Wireless (uses AT&T/ TMobile)
AT&T (Includes GoPhone Prepaid, Dobson Cellular, Edge Wireless and Centennial Wireless)
Cellular One of East Central Illinois
Cellular One of East Arizona
Cellular One Nation
Cellular One TXOK
Chariton Valley Wireless
Cincinnati Bell Wireless
Commnet Wireless (also uses CDMA)
Consumer Cellular (uses AT&T towers)
GCI Wireless (also uses CDMA)
GTC Wireless (uses AT&T towers)
Jolt Wireless (uses AT&T towers)
Locus Mobile (uses CDMA, Verizon & AT&T towers)
Long Lines Wireless
Mobal Freedom (uses AT&T towers)
Pure Prepaid (uses AT&T towers)
Pure Talk USA (uses AT&T towers)
Simple Mobile (uses T-Mobile towers)
Shaka Mobile (also uses CDMA, Verizon & Sprint towers)
Telecom North America Mobile Inc
TracFone Wireless (also uses CDMA, AT&T, Verizon, Sprint, US Cellular and T-Mobile towers)
Tru (uses T-Mobile towers)
Wal-Mart Family Mobile (uses T-Mobile towers)
West Central Wireless
Can you make calls with this model if you use a sim card?
Also can you get updates on WiFi only if you do not buy a sim card?
Has anyone bought this model from a recent woot? Any feedback?
You would need an application like Skype to make calls. It is not a telephone.
You can get updates over Wi-Fi with no problems.
Ditto to BigD. Bought the Samsung Tab 2 for traveling. A friend incurred $600 in roaming. I got a phone number from Google Voice which I think can be used to buy minutes in various areas (with sim card) so you know that can’t happen. The unlocked are a bit cheaper on Amazon if you don’t need this.