BigTinzIf that's the questions you're asking then I seriously think this product isn't targeted at you. It's very likely that FLAC, ALAC or DSD just sounds like gibberish to you. For the most part, this product doesn't do anything that your phone can't do.
A pretty good analogy is that for commuting to work every day, a Ferrari doesn't do anything that my crappy hatchback can't also do.
BigTinzIt has 64 GB internal memory + a micro SD slot, so it can store a decent amount of high def music without filling up your phone's SD card. Plus it has FM radio capability (which the galaxy has but tends to be blocked by the wireless provider) and its own battery which saves you from having a dead phone from listening to music.
TomSawyerPlus its independent battery has a way longer lifespan than your phone's battery, largely in part to it being dedicated to playing music and not to being, well, a mini computer/phone.
blackcatdownIn the specific case of high end Galaxy phones (not sure in the most recent model) they come with very capable Wolfson DAC´s and Android supports FLAC without problems, so if you are a Galaxy user you probably don´t need this or won´t feel this as an upgrade in most cases.