What makes the fps great: Camera shakes when running. Camera shakes when shooting. Camera shakes when reloading. Making it more action paked. Sliding jumping fast movement Most important high fov.
Polyfield was definitely a gud game when I had a low end device with 2gb ram but I got a new phone now so I play combat master which is great too but it's getting boring since i have played it for like 6 months now completed the 30days mission challenge played different modes several times.
For me its easy to make an fps action paked game like combat master, some devs only focus on their online big games, well im an inspiring person ambition to make the best offline games, (im becoming and still learning)