Ever buy an unlocked BlackBerry and realize some third party apps that require internet connection don’t work?  A big reason why they don’t work is because it’s most likely that your APN/TCP settings are incorrect.  For example, if you buy an unlocked T-Mobile BlackBerry and use your AT&T sim card, you’ll need to change up those settings, as they’re defaulted for T-Mobile.  I recently went through the same and figured it would be good to share some APN/TCP settings for both AT&T and T-Mobile (even though they will be merged soon enough).

T-Mobile – Has TCP/IP

• APN: wap.voicestream.com
• Username: leave blank
• Password: leave blank

AT&T

• APN: wap.cingular
• Username: wap@cingulargprs.com
• Password: CINGULAR1

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