Sadly the Nexus 5 won't support the 4G in India, as the 4G spectrum allocated here so far is the 2300 Mhz band which none of the top end smartphones
supports in India yet. But I guess till the time all those Lazy BWA Spectrum winner will pull their Shit together to offer a running network, compatible handsets too will be available.
Ok. Just curious... How does 4G LTE work here in India? Do you get a SIM card? If yes... How are you going to make calls using it when Airtel does not have the rights to offer voice over 4G LTE in India? :
From what I understand 4G rights were not sold like usual here in India. They were sold for data not voice.
From what I have read they are using CSFB (Circuit Switched Fallback System) for enabling Voice, which makes the device "falls back" to the 3G or 2G network to complete the call.