According to Fudzilla, Qualcomm Senior Director of Public Relations Jon Carvill recently said that "there are no plans for a Snapdragon 815 processor."
OK, so the Snapdragon 815 doesn't exist, but this doesn't mean the current SD 810 - used by flagship devices like the HTC One M9, or the Sony Xperia Z4 Tablet - will remain Qualcomm's flagship chipset for long. As announced earlier this month during MWC 2015, the company is getting ready to launch a new powerful CPU, the Snapdragon 820, expecting to start sampling it in the second half of the year. It remains to be seen if the SD 820 will be ready for devices to start using it before the end of 2015.
Like the Snapdragon 810, the 820 is a 64-bit octa-core processor, and it will almost certainly power various high-end Android and Windows smartphones (and tablets).
source: Fudzilla via GSM Arena