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MIUI8 Global Beta ROM 7.3.9 Full Changelog and Download Links - MIUI General - Mi Community - Xiaomi - Mobile https://c.mi.com/thread-152728-1-0.html
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There has to be a Android upgrade to avail VoLTE.
MI4i is not getting VoLTE support unless there is an Android upgrade to 5.1.1. This phone has an x64 bit architecture.So there is a chance of getting VoLTE in the future.Also this Processesor is capable of much more features to run flawlessly. As Qualcomm Snapdragon 615 processor supports VoLTE feature,stop telling our forum members that Mi4i can't handle VoLTE feature because of it's processor and other hardware problems.
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