A few days ago Samsung launched their latest phones, the Galaxy Note 5 and the Galaxy S6 edge+. Both use a similar 5.7" QHD (2560x1440, 518 PPI) Super AMOLED displays (the S6 Edge+ uses a plastic-OLED curved over the edges). Display measurement experts DisplayMate posted an in-depth review of the display used in these new phones (they tested pre-release production units).
Unsurprisingly, DisplayMate found that these are the best mobile displays they ever tested - there are many significant improvements over both the Galaxy Note 4 (which was previously crowned as the best mobile display) and the Galaxy S6. The most impressive improvements are in peak brightness, screen readability in high ambient light and the power efficiency.
The Note 5 can be very bright - up to 861 nits - the brightest display ever tested at DisplayMate. In high ambient light this results in high contrast (again, the highest contrast under high ambient light ever tested on a mobile device). The Note 5 is 21% more efficient than the Note 4 - and consumes less power even though it is much brighter.
Compared to the iPhone 6 Plus, the Note 5 is 37% more efficient on images that have a 50% average picture level. The current power efficient crossover between OLED and LCD displays are at 67% APL, and DisplayMate estimates that OLEDs will be more efficient than LCDs in total power efficiency in the near future. The flexible OLED used in the S6 Edge+ performs the same as the rigid OLED in the Note 5.