If its Note 4, not Note 3 , is LTE enabled in India... Apart from Airtel, who else started LTE in India, i think Airtel using 2300 MHz (band 40), if its present in ur Note4 it will work, another frequency is going to be 1800MHz(Band 3) , i think Reliance is going with that...not sure... so at present , in India these 2 LTE bands are going to be on , Note 4 should have these inside .. u havent mentioned whcich network u r using.. iPhone is the only phone supports most of the LTE bands, so if u go with sim free one, anywhere in the world LTE will work, (3G and 2G always work in almost all supported phones anywhere). Next phone with many LTE bands are Oneplus (look at my avatar) and Oppo's phones, Note 4 (samsung has increased bands in Note4 ) Indian model- N910G has LTE 700 / 850 / 900 / 1700 / 1800 / 1900 / 2100 / 2600 TD-LTE 2300 / 2600 (Bands 1, 2, 3, 4, 5, 7, 8, 28, 38, 40). So you can see 2300MHz in there.... so it should work with a 4G sim from Airtel or Reliance or whoever has LTE now rolled out... also you have to understand that its not network name, the LTE band the network using should be present in the hardware and the file u mentioned. Manufacturers can disable LTE bands by simply not listing the band in the software. If its not present in Hardware(radio) , no way you can enable in software. So as far as your Note 4 is concerned , it should be working as long as you put in a 4G sim from netowork offering it...