Samsung is trying to acquire the market of mid range devices which they lost with launch of poor devices like galaxy grand range before.
The 4g capability gives this device a bump as we compare to the other devices, since, we all know that the 4g is the future in indian telecom and big companies like airtel, idea and reliance have already started their 4g services in india. So, anyone who wants to buy a phone now should go for the 4g phone.
Oneplus x is the only competition if j7 currently in the market, but the j7 marketed so much that it can easily defeat oneplus x. So lets see what happens in the comming future.