In case you're wondering "why the fuck did you do that?" it's all about having a device with a dedicated DAC.
Basically, modern smartphones use integrated audio. This makes them cheaper to produce but makes the audio quality pretty bad, especially if you enjoy lossless audio.
This beauty here has an integrated DAC (digital analogue converter). Essentially, although audio data is stored digitally these days, audio itself is still analogue. So a DAC converts digital files to analogue audio that plays through your headphones.
But as mentioned, smartphones these days don't have dedicated DACs. The integrated audio converters are kinda sorta alright if all you listen to is low quality compressed music through cheap headphones or overpriced AirPods (same audio quality - yes, it is) but if you're playing lossless audio from say Tidal, Apple Music, or FLAC files, it'll sound shit.
Enter this little beauty. It can play music from a microSD, and since it has WiFi and Android it can also play lossless audio from streaming services that offer it (and you can download albums you like from said services, of course).
Basically if you properly like music and wanna hear it in proper quality this is a must.
I actually have an older version of this that's about 4-5 years old and is basically the "dumb" version. No Android or apps. It's like a basic iPod type deal, but still focused on lossless audio.
However I got one of these because I find myself switching between my Walkman and phone if I wanna stream, and even though I have lossless streaming, I'm not getting the most of it from my phone.
This little beauty should be the best of both worlds. Reviews are all glowing so I'm looking forward to it.