Cuban.... come on brother. It's a simple number progression. Samsung Galaxy S, S2, S3, S4... you see where I'm going here. I'm going to step out on a limb as say their next phones will be S8, S9, and S10.
What you think you see is purely coincidence. One that you see will disappear if Apple continues their naming convention. The iP7 will match the S8 equivalent. The iP7S will match the S9 equivalent. The iP8 will match the S10... and so on.
This. Exactly.
Apple has been all over the board with phone names: 3G, 3GS, 5S, 5C, SE.
Samsung has been completely predictable so far: S, S2, S3, S4,S5, S6,S7
Neither is better than the other. But saying Samsung copied Apple's naming is pushing it a bit.