Samsung Exynos 7420 Advantages
Better graphics card performance FLOPS (0.1976 TFLOPS vs 0.0091 TFLOPS )
Larger memory bandwidth (24.8GB/s vs 6.4GB/s)
Higher Frequency (2100MHz vs 1500MHz)
More modern manufacturing process (14nm vs 28nm)
MediaTek MT6739 Advantages
Released 2 years and 5 months late