Qualcomm Snapdragon 821 Advantages
Better graphics card performance FLOPS (0.3343 TFLOPS vs 0.0394 TFLOPS )
Higher Frequency (2342MHz vs 2000MHz)
Samsung Exynos 850 Advantages
More modern manufacturing process (8nm vs 14nm)
Lower TDP (3W vs 11W)
Released 3 years and 9 months late