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I wonder if this codec will be added to the 4 or the 4S, I was expecting this to come with the iPhone 4 but 2 years of waiting and Apple have finally caught on with international standards it seems, just a shame there limiting it to the iPhone 5.
 
I just read in the news this morning that T-Mobile has enabled Adaptive Multi-Rate Wide Band (AMR-WB) functionality on its GSM cellphone network here in the USA--in short, HD Voice is now active on T-Mobile. They said that the Samsung Galaxy S III and HTC One S will support it "out of the box" now, and any cellphone T-Mobile sells that supports AMR-WB will have full HD Voice functionality.

I believe that the iPhone 5 does support AMR-WB, and since T-Mobile has said they may offer the iPhone 5 by late spring 2013, that could mean any iPhone 5 running "officially" on T-Mobile will support HD Voice, which means a huge leap up in call sound quality.
 
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