MediaTek Helio G90T Advantages
More modern manufacturing process (12nm vs 14nm)
Lower TDP (5W vs 11W)
Released 2 years and 11 months late
Qualcomm Snapdragon 821 Advantages
Better graphics card performance FLOPS (0.3343 TFLOPS vs 0.2304 TFLOPS )
Higher Frequency (2342MHz vs 2050MHz)