Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.
Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.
Dynamic range test data courtesy of DxO Mark.GX850 test data on DxO Mark G1X Mark II test data on DxO Mark
Wider, longer, faster lens than predecessor, with good overall optical quality; Faster AF performance; Closer macro shooting; Built-in Wi-Fi and NFC with remote shooting; Decent JPEG burst performance; Excellent build quality.
Localized flare issue when wide open; No real net improvement in image quality over predecessor; Slow burst mode when shooting RAW files; Poor battery life; Video quality is so-so (not like Canon DSLRs).
Impressive image quality; Sleek design; 4K video recording; Good overall performance; Tilting touchscreen; Enjoyable user experience.
No EVF; No hot shoe, Short 4K clip limit; MicroSD card slot, Poor battery life.