Ugh. I just dug out my Zenfone 6 to use as a DAP. I do wish there was something smaller though...
I almost forgot how cool it is. Notification LED, rear fingerprint reader, SD card slot, dual SIM, extra programmable physical button, flip-around camera, headphone jack w/ HQ DAC. It's pretty much peak hardware (other than being too big and heavy). But unfortunately ASUS abandoned the software after about a year.