Need phone for US & other countries

[vpelton]

I'm a newbie on this subject so need basic info. I've read all about sim cards & cdma/gsm but all the info assumes a basic level of understanding that I don't have. I need the basics.

I live in the US (using Verison) & will be travelling to Brazil & want to upgrade my Android phone so wanted one that will work all over the world (or at least many countries). I was told to get a "global" phone (like the [FONT=&quot]droid 2 global[/FONT]) since it works on both cdma & gsm. I was told that's all I should be concerned about. But this guy said there were only 5 such phones for the Verizon service & 3 were not made any more.

But what does the sim card have to do with anything? Somehow I need a sim card for a specific country? If I bought a sim card for a country, will it work in any phone with a sim slot? Do I still have to be concerned about cdma/gsm?

Summary: I live in the US using Verizon & want to travel with my phone. What do I have to look for in a new phone so it will work in many countries?

 

[chanchan05]

Basically, a quad-band or penta-band GSM phone will work almost anywhere for calls and SMS. The problem will be data. The US uses a different 3G network from the rest of the world, and in some countries, CDMA networks do not exist.

Check this link for example, the international version of the Galaxy S III:
Samsung I9300 Galaxy S III - Full phone specifications

You will see these numbers at the top:
2G Network GSM 850 / 900 / 1800 / 1900
3G Network HSDPA 850 / 900 / 1900 / 2100

Those represent the frequency bands that the phone operates in. Basically, a carrier network like TMobile must have the same frequencies as the phone operates in so that it can work.

You can check here:
GSM World Coverage Map- GSM Country List by frequency bands

Based on that table, and the information I posted, you can see that the phone will work on any GSM networks in the US, but only supports AT&T and Cordova for 3G network. You just have to compare the sets of numbers available per country.

Strictly speaking, any country you go to, you can have GSM calling and SMS capability if you have a quad band phone. Only data with 3G speeds is questionable, depending on carrier.

 

[vpelton]

Whoa ... complicated. Thanks so much for all the info, but, of course, more questions.

You say "quad GSM" will work anywhere (call/SMS). But the Verizon guy told me they use CDMA, NOT GSM. Or was he talking about data? Also, if such a phone will work anywhere, then why do I have to buy a phone from the Verizon section in the store, & not the TMobile section? Again, is it because of the data?

When you say "quad", I assume you mean 4 bands, like "GSM 850 / 900 / 1800 / 1900", right?

Which numbers do I look at for call/SMS & which for data? Is 2G call/SMS & 3G/4G data?

Also had questions about the World Map. For the first 4 columns, that's for calls/SMS, right? Then they have 3G/4G for data? But for USA, Verizon, it just says 4G. But it must work on 3G also, right?

In your Samsung example, you say for 3G, you can only use it with 2 carriers. But the phone lists 2100 which is used for all the 3G carriers. For 4G, the phone lists LTE. I thought 4G equals LTE.

On the world map, it shows Verizon with 4G, does that mean LTE?

Brazil has some 3G bands listed, but Verizon is not listed under 3G so how do I know what Verizon uses for 3G?

If the 3G of the phone is not compatible with the 3G of the country, can I still get data, just at a slower speed?

Also, what's the whole thing about the sim card? Do you need that for functionality, or does that just determine how you are billed? For example, if I got a quad phone & just want to make calls & don't mind paying international rates with my USA Verizon plan, do I have to do anything with a sim card?

Thanks so much for your help.

 

[ch3mn3y]

When you say "quad", I assume you mean 4 bands, like "GSM 850 / 900 / 1800 / 1900", right?

Which numbers do I look at for call/SMS & which for data? Is 2G call/SMS & 3G/4G data?

For call/sms are all - 2g/3g/4g i think even 1g (if it exists) let u call/text. Data starts from 2g but its very slow

Also had questions about the World Map. For the first 4 columns, that's for calls/SMS, right? Then they have 3G/4G for data? But for USA, Verizon, it just says 4G. But it must work on 3G also, right?

U see it right. 3g/4g means speed of data.
Verizon will work only on cdma 3g, it wont work on GSM/umts 3g, which are in most countries.

In your Samsung example, you say for 3G, you can only use it with 2 carriers. But the phone lists 2100 which is used for all the 3G carriers. For 4G, the phone lists LTE. I thought 4G equals LTE.

In his example s2 can use only 2g/3g carriers.
S2 has LTE only when its bought in countries with 4g (verizon has "galaxy s2 4g, made for them by samsung)

On the world map, it shows Verizon with 4G, does that mean LTE?

lte or wimax or both

Brazil has some 3G bands listed, but Verizon is not listed under 3G so how do I know what Verizon uses for 3G?

Verizon uses CDMA for 3g, Brazil carriers use GSM/UMTS

If the 3G of the phone is not compatible with the 3G of the country, can I still get data, just at a slower speed?

Only if it is compatibile with 2g

Also, what's the whole thing about the sim card? Do you need that for functionality, or does that just determine how you are billed? For example, if I got a quad phone & just want to make calls & don't mind paying international rates with my USA Verizon plan, do I have to do anything with a sim card?

If u dont want to pay international rates u need sim card from carrier from country where u are. U need to change simcard everytime. But sometimes carrier can be in 2 or more countries and has no or small rates there.


I think u should look for phone which frequncies are 850 and 1900 cause in moat countries carriers work on them (but eg. Verizon doesnt). U need gsm/umts phone i think.

 

[chanchan05]

1. To clarify a quadband phone indeed refers to a phone that is capable of using four frequencies.

2. A Verizon CDMA phone cannot be used as a world phone because CDMA is not popular outside of North America I am aware of. So if you want to stay with Verizon but use a world phone, it needs to be compatible to both CDMA and GSM. T-Mobile on the other hand is a GSM Network, meaning any quad-band phone from them can work for calls and SMS around the globe. A Verizon phone will not work for example in Singapore or HK, but a TMobile phone will.

3. Calls and SMS can go through either 2G or 3G. I am not sure about 4G, but I think yes as well.

4. In the world map, the first four columns show the 2G bands available in that country. Basically, if your phone has the bands for that country, you can make calls and send SMS there and use data as well but at 2G speeds (about 56-200kbps max). For the next column, it shows the bands of 3G used per network in that country. If your phone matches the bands of a particular network, then it means you can use the 3G frequency of that network as well for data (you get 500kbps to a possible max of 14mbps). Same goes for 4G column.

5. Some carriers have a 900/2100, or a 700/2100 3G band. Someone once told me, you might need both to have 3G work (uplink and downlink), so I can't be sure if it will work in other networks. LTE is one of two different 4G technologies (the other being WiMax). The SGS3 I used in example also lists LTE as regional, so not all SGS3 has LTE. If you manage to get one, it will work for the LTE of a US carrier.

6. Yes if 3G of the phone is not compatible with 3G of the country, you can only get 2G speeds.

7. CDMA phones do not use SIM cards. GSM phones does. CDMA phones need an activation from the network before they can be used, basically they are locked into that network. An unlocked GSM phone can use any network out of the box by just inserting the SIM for that particular network. Each SIM card also has a different phone number. A GSM phone will not work without a SIM card because that's what allows it to connect to a carrier. For example, there are two major carriers in my country. Lets call them Network 1 and Network 2. I am on Network 1. But I want to use Network 2 for a time. Its as easy as removing the Network SIM 1 from my phone and inserting Network 2 SIM, and there you go, I have changed networks. Of course that is if your phone is not locked for use to a specific network. If it is, you can only use Network 1 sims for the phone, but getting your phone number changed is also just simply replacing the SIM card.

 

[vpelton]

Tons of info here, thanks. I'm learning, but still have more questions.

The Verizon guy said I could use HTC DROID Incredible 2 so I looked that up on the link given. It has:

2G Network CDMA 800 / 1900
GSM 850 / 900 / 1800 / 1900
3G Network CDMA2000 1xEV-DO
HSDPA 900 / 2100


While Brazil has:

Brazil
2G = 900 1800 1900 850
3G = 2100, 850


For Brazil, the 2G is GSM. Is the 3G GSM also? So looks like this phone will work for calls/SMS, is that right? The 3G will not work in Brazil. But, I can get data via the 2G network (slowly), right? What's "1xEV-DO" & "HSDPA"?

For this phone, it as 2 freq listed for CDMA. Is CDMA always that way? So you'd never have a quad band CDMA phone? It has 1900 listed for both CDMA & GSM. Is that the same thing? Or, is it the same freq but the details are different so they are not compatible?

On to SIM cards. This phone will work in the USA on Verizon. How do I know if the phone is locked or unlocked? Do I just pay extra to unlock it? If I want to use it in Brazil, the freq bands are good, but do I need a different SIM card? If the SIM card lets me use a different carrier, am I billed via the new carrier? But the Verizon guy said I could use this phone in Brazil & would be charged by Verizon with international rates, so sounds like I'd still be on Verizon.

If I have this right, then I'd like to look at ALL phones that have both CDMA & GSM. Is there a place that has such a list? Of the 4 phones the Verizon guy listed, this is the only one with Android & without a physical keyboard.

Thanks for all the wonderful info. It helps a tremendous amount.

 

[chanchan05]

Well, generally, SIM card slots don't exist on CDMA phones. So ife Brazil networks is GSM only, your phone won't work since they don't have a CDMA network. You can only connect to a GSM network if you have their SIM.

As for a list of such combination phones, I have no idea.

 

[vpelton]

But looks like the HTC DROID Incredible 2 does have GSM, at least on 2G:

2G Network CDMA 800 / 1900
GSM 850 / 900 / 1800 / 1900

3G Network CDMA2000 1xEV-DO
HSDPA 900 / 2100

It has a SIM card. So my understanding is that I could use it for calls/SMS & (slow) data. Is that right?

 

[chanchan05]

Oh ok, it has a SIM card. Yep it should work. Provided you get Verizon to unlock it so that you can put a non Verizon SIM card into it.

 

[vpelton]

Sounds good. Just looking at my options, I think Verizon said I could just use the phone as is in Brazil & pay international rates ($2/min). Will that work? Somehow the carrier in Brazil will allow my phone to work & somehow Verizon will bill me for it?

Or, if I want to buy a SIM card, could I buy it here in the US (one less thing to worry about on the trip), or do people generally buy it in the destination country? If the latter, I assume that's probably done in the airport?

 

[chanchan05]

If Verizon told you that you can use it in Brazil with roaming rates, they have an agreement with a local network. Rates will be expensive though.

As for SIM, it depends on the country. Here is SEA for example, SIM cards can be bought at almost any mall, supermarket or those loading center kiosks carriers here have everywhere.

 

[vpelton]

Thanks for all the info. It was a huge help.

 

[vpelton]

Still don't quite understand the 3G compatibility info. For Brazil is has:

3G 2100, 3G 850

For the Motorola Droid RAZR XT912 is has:

HSDPA 850 / 900 / 1900 / 2100
CDMA2000 1xEV-DO

So, the band numbers are the same, but is HSDPA the same as, or compatible with GSM? The phone is compatible on 2G, but it would be nice to have it compatible on 3G also.

 

[chanchan05]

HSDPA is 3.5G. It would work.

 

[vpelton]

Just got more info from Verizon about my new Motorola Droid RAZR phone.

First off, the GSM website for this phone has:

Motorola DROID RAZR XT912
2G Network GSM 850 / 900 / 1800 / 1900
CDMA 800 / 1900
3G Network HSDPA 850 / 900 / 1900 / 2100
CDMA2000 1xEV-DO

So you would think it would work in Brazil (using GSM). But the Verizon guy said it would not. I pressed him on the issue & he transferred me to "someone who knows about global phones". The new guy said the phone currently only works on CDMA but they are planning an upgrade to the OS "any day now" that will allow the phone to also work with GSM & HSDPA. He said the GSM website isn't wrong, it's just looking ahead.

That would be great, but I'm surprised the change only needs a software change. It doesn't need any different hardware? If it's just SW, I would think companies would make it available on more phones (good selling point).

 

[Hadron]

It does need the hardware. I read this as the phone has the hardware, but VZ software doesn't yet let it use that hardware for roaming.

 

[vpelton]

Now that makes sense. Thanks.