Interesting observation regarding unlocked phone

[daneoni]

So i just got back from a friends house. He has an unlocked iPhone he got off ebay. Naturally i start playing with it and everything works peachy. I noticed however that the iPhone recognises his phone number. For example, when i launch the phone app, his number shows at the top and says "My Number:+44 78########".

Also when he docks the phone with iTunes, iTunes recognises and displays his phone number "4478########" instead of n/a. However when i swapped out the sim and put in my own, it didn't recognise the number and iTunes just shows n/a. Curious as to why this is....what's so special about my friends SIM?

By the way he's on a T-Mobile Pay & Go Tariff whilst i am on a O2 Pay Monthly Tariff.

 

[hollerz]

This is the same with mine, on Vodafone PAYG, it said n/a, but with my new T-Mobile SIM it says 44079..... Not sure what makes T-Mobile so special!

 

[daneoni]

I see. An educated guess is T-mobile encode actual numbers into their SIM cards in addition to other stuff whilst the other SIMs are just tools for connecting to the network nothing more

 

[gallinger]

I have a Rogers SIM and it allows me to view my Number from the phone.app and aso in iTunes. never thought anything of it.

 

[daneoni]

I have a Rogers SIM and it allows me to view my Number from the phone.app and aso in iTunes. never thought anything of it.

Majority dont have their numbers showing. Must be a network technology thing.

 

[carfac]

My unlocked T-Mo USA phone shows the correct phone number in iPhone and iTunes.