Dual-SIM Phones

This article is still in progress.

Some comments first:

• I won't buy a dual-sim phone for more than $300. Actually one hundred something is the comfortable amount. Most of us use a dual-sim phone to save money; it does not make sense to spend too much money to save money, does it?
• Moto G XT1033 is the only one that has 3G support on both SIM slots. Not at the same time, of course, no device can do that. All others can have 3G on SIM1 only. This is not a big deal though - just use a dual-SIM adapter.
• They all can dual standby. For example, you can use data on SIM1 while still able to receive calls on SIM2.
• They all can do voice calls and use 2G data in all countries.
• If you need 3G on other countries such as China etc., you need at least 2100. If you need AT&T 3G, you need 850/1900.  If you need T-Mobile 3G, you'd better get 1700 (some locations now adopt 1900 as well).
• Lenovo K910 is the only one that has both 1700 and 2100 (it has CDMA/EVDO too!).  This means: if you need full coverage on T-Mobile and meanwhile need to use 3G in China and other countries, this is your only option.

I did a search in Amazon and these were interesting to me for their 3G coverage:

The followings work on 3G on AT&T, T-Mobile and in other countries

Lenovo Vibe Z K910
850/900/1700/1900/2100 CDMA/EVDO
5.5"
$272

The followings work on 3G on AT&T, T-Mobile (1900 area only) and in other countries

Galaxy S4 Mini Duos GT-i9192
850 / 900 / 1900 / 2100-LTE
4.3"
$250

Lg G Pro Lite Dual D686
850 / 900 / 1900 / 2100
5.5"
$200

LG OPTIMUS L7 II DUAL P715
900 / 1900 / 2100
4.3"
$160

BLU Life One L120
850, 1900, 2100
5.0"
$180

Motorola MOTO G XT1033
850 / 900 / 1900 / 2100
4.5"
$220

iRulu Newest V1 Phone
850/1900/2100
5.5"
$135

Samsung Galaxy S Duos 2 S7582L
850/900 / 2100
4.0"
$142

The followings work on 3G on AT&T and T-Mobile (all area)

Posh Mobile Titan HD E500
850/1700/1900
5.0"
$180

BLU Studio 5.0 II
850/1700/1900
5.0"
$112

BLU Studio 5.0C
850/1700/1900
5.0"
$108