I had already tried VLC API and it works very well but due to VLC API size of apk increases incredibly high upto 70 MB. I also tried with Vitamio but it gives error after target sdk 22. Also I find out that ExoPlayer does not support RTSP urls, so what to use right now for RTSP which gives a better result than VLC
After exploring so much, I got the solution to this problem. Now I am using VXG SDK which gives the perfect result to my solution. My apk size is almost reduced to half to that of VLC and also the app works on every software and hardware platform very well.