There are two models of our device RG740. The RG740A (also referred to as RG740 Grand Tour) and the RG740B.

The RG740A has: 16GB ROM, 2GB RAM, MSM8916 Chipset, Android 5.1.1
The RG740B has: 32GB ROM, 3GB RAM, MSM8937 Chipset, Android 7.1.2

You can find out which model you have by going to Settings > About Phone > Model