If I was you I would just buy a prepaid sim card from mexico so its really cheap for you and use Google voice on top of that so you have a us number when calling back to the US but it wont cost you $0.17 a minute because I think google voice will get you mexico number to call then it will use a US number for the person your calling. I think thats how it work if im wrong someone let me know.
[GUIDE] Set up Verizon Galaxy S3 as World GSM Phone (confirmed working) - Page 11 - xda-developers
This is from XDA
Thanks to Beemer533 for informing me that I can use Titanium Backup Pro (which I have always had) to set APN Manager Pro as a system app, I have a revised and simplified method for this process. But I need someone to test and see if the steps work correctly, as I am no longer overseas to test.
If you can, follow the steps in section A and B (and C if you can) and let me know if this all works OK...especially if there are no phone call out problems. If I can get working confirmation, I will modify the OP to reflect this process. Let me know where you are, and who your provider is.
THANKS!!!!
A: Preliminary steps that were done before leaving the US:
a1 – From Google Play store install the following apps if you do not have them: APN Manager Pro (81 Square), Phone Info (sc@taiwan), Titanium Backup Pro , ES File Explorer and Open Signal Maps. You may have to pay a few bucks for some of these pro versions, but they are required.
a2 – In Titanium Backup Pro, go to Backup/Restore, find and “long select” APN Manager Pro, and then select “Convert to system app”.
a3 – Open APN Manager Pro, select Insert APN, and input the data needed from your desired service provider (see note 1 below for help). When done, go to APN List and make sure your current APN’s and the new APN’s are both there. What I did was to leave the US with several options for each country I was going to visit already loaded into the APN list so I could be ready for several possible providers. At this point, your phone should still be fully functional in the US with Verizon LTE.
B: When overseas, I did the following steps to go from LTE to GSM:
b1 – Turn off phone, pull out battery and put in micro SIM from your foreign country. DON’T LOSE YOUR VERIZON LTE SIM! Turn phone back on and turn off Wi-Fi.
b2 – Use Phone Info app to change preferred network type "Global" (click on Device Information and scroll down to the first box to change). Some have reported that other choices were needed for their providers, so you may have to experiment.
b3 – Go to Settings>More Settings>Mobile Network>Access Point Names and select the correct APN. I believe that only APN’s that your SIM recognizes will show on this list. (If it’s not here, go back to step a3 and enter the needed APN data).
b4 – Reboot phone. You should have the SIM card working for phone and data.
C: To return to Verizon LTE:
c1 – Use Phone Info app to change preferred network to “LTE/CDMA/EvDo” (click on Device Information and scroll down to the first box to change).
c2 – Turn off Wi-Fi, pull battery and put Verizon LTE micro SIM card back in.
c3 – Power up phone (at this point you might be working properly already, and you are good to go!)
c4 – If needed, go to Settings>More Settings>Mobile Network>Access Point Names and select LTE-Verizon Internet (which is my default here in North Carolina).
Notes and Troubleshooting Issues:
1. Below are several sites to check if you do not know the correct information. I cannot guarantee that this information is current. You may only need to enter some of this information to get data working (I did not try phone or MMS use). In some cases it may be as little as just the APN Name to display and the correct APN (sometimes referred to as GPRS APN), while other providers may require the user names or passwords or more for full functionality. Please report your successful requirements in the thread.
World Wide Mobile Phone Settings
MCC/MNC code
Mobile APN Setting to use GPRS
APN Setting for WorldWide Mobile Networks
h t t p ://www.flexispy.com/Mobile%20APN%20Setting%20to%20use%20GPRS.htm
h t t p ://blog.rebelsimcard.com/worldwide-network-gprsedge3g-network-apn-settings.htm
2. I highly suggest that you use Open Titanium Backup Pro and backup your phone apps and data. Go to Backup/Restore; then select the check mark in the upper right corner; then select RUN "Backup all user apps and system data"; and then select the green check mark in the upper right corner. Let this run until complete. You can restore any of your apps from here in the future.
3. I highly suggest that people use the Open Signal Maps widget that comes with this app, and install it in a 1x2 format on one of your screens. This shows exactly what is happening as far as provider, signal strength, and type of signal. This is where I could see that I got 3g, 3.5g and 4g service from time to time in Moscow and Helsinki. I keep this on my home page here in the US.
4. When using your phone in the US or overseas with a non-verizon SIM card, you have a constant icon warning in the notification bar referring to a "Non-Verizon SIM". If this bothers you and you want to remove it, the answer is to freeze or delete the app Setup wizard 1.0 (its icon is a red check mark with a magic wand). Using Titanium Backup, freeze or delete Setup wizard 1.0; or if you freeze/delete with AntTek App Manager, it is the second listed Setup wizard and contains 24.00kb. The app contains very little data in the database (three csv files with nothing of interest), and hopefully can be safely frozen. I have no idea why it is in the phone to begin with.
5. I also suggest learning the great features of ES File Explorer. If will allow you to easily get to your all your files (including system and root). Open it and go to menu>settings; then check "up to root", "root explorer", "mount file system" and "backup system app". Now you have full access and control of your phone files. The external card is found at /mnt/extSdCard, while the internal SD card is at /mnt/sdcard. You can set favorites to get to places you want to visit fast, and that is a plus to this file program.
6. Some phones have the option to check the following: Go to Settings>More Settings>Mobile Network (if available)>then the first instance of Network Mode (before Access Point Names), and make sure it says Global mode or another choice that works for your provider (If not, go back to step b2).
7. Some phones have the option to check the following: Go to Settings>More Settings>Mobile Network (if available)>then the second instance of Network Mode (after Access Point Names), and make sure it says GSM/WCDMA (Auto Mode), at least that is what I needed in Europe. Some providers may need other selections and you may have to experiment.
8. There have been reports of problems with the phone app crashing using the prior, more complex method. If this happens, try restoring your "com.android.phone" app with Titanium Backup. I'm still looking for confirmation that this fixes any issues, so please post to the thread if you have this problem and let us know if this fix works, or if it does not.
Thanks for Beemer533 for making aware that I can use Titanium Backup to make App Manager Pro a system app! This is the way I had changed APN’s with my old HTC Incredible 2.
Please provide feedback on your success or problems.
And if this helps...give a thanks!!
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