Apple A12 Bionic Advantages
Lower TDP (6W vs 8W)
Apple A17 Pro Advantages
Better graphics card performance FLOPS (2.1472 TFLOPS vs 0.576 TFLOPS )
Larger memory bandwidth (51.2GB/s vs 34.1GB/s)
Higher Frequency (3780MHz vs 2490MHz)
More modern manufacturing process (3nm vs 7nm)
Released 5 years late