To use Airtel 4G sim in a 3G enabled phone is something rare. Firstly, what’s 4G? According to Wikipedia it is the fourth generation of broadband cellular network technology. It is much faster than 3G in all aspects and will soon eradicate 3G broadband soon.
However, some smartphones don’t have 4G network especially the phones that were in vogue before the advent of 4G. This has caused lots of problem for people and this led to the question How to use Airtel 4G sim in 3G phone?. We have done a lot of research to see the possibility but for now, it won’t be possible because when you insert a 4G sim into a 3G enabled phone it will display only a 3G network.