I will repeat, one of the CONS of the EXOGAL units is the fact that they do NOT have any physical Controls. the remote works when in direct line of sight w/ the unit, the screen is small and hard to see. The app works fine if you have a device that can download the software, the BT is ok. You should not be fiddling w/ your DAC during a listening session and this one is not fun to fiddle w/. I prefer to control volume from my streamer or a pre-amp, or any way other than the EXOGAL Comet DAC. If you have NO remote and NO App you will own a brick, the DAC does NOT have any controls otherwise to power it on or use it, might as well throw it out.
Warning, SUBJECTIVE OPINION forthcoming → As far as comparisons go to performance, I am intimately familiar w/ the EXOGAL relative to a few other brands. I have no stake in you liking a unit or not and don’t care, but folks are comparing performance of these units incorrectly. They are more in-line w/ $5K++ tier units in performance, I’ll back my words up w/ listening sessions all day long. (MSRP pricing) This is NOT a negative comment to anyone here, but the used price of this unit is not in line w/ its performance ability which is why they are a good value if you find one that keeps working trouble free for a few years. 
The sound quality is fairly neutral, they are imaging freaks and promote a solid wide soundstage. If the front end is good enough, the background blackness is liquid and enhances instrument separation. They perform best being fed AES or BNC from a dedicated streamer source. The USB implementation will pick up noises from your source if they are present.
The company has gone bankrupt and you will have no support if your unit has issues, this is common in the used market thus you will be taking a chance on your money spent.