I just purchased a Samsung Chromebook Plus recently. In the Chromebook files app I have noticed that DNG files shot with my camera show up fine, however those shot with my phone do not (the phone DNG files themselves show up, however, they don't show a thumbnail image and won't open). The camera files had been imported into Lightroom and converted to DNG from the raw camera files (Panasonic FZ and Canon) when I had a PC. My phone is a Samsung Galaxy S7 Edge. I set the camera to pro mode and the files get saved as DNG. I have also tried this with my wife's Galaxy Note 5 with the same results. I thought that the DNG format was universal like JPG, PDF, etc. I have posted this same question to the Google Chromebook Forum and have tried to research it to no avail.
Thank You for your help, Jerry
The DNG format is supposed to be universal as long as whatever device is creating the DNG file was designed to create the DNG specifically conforming to the standard specified by Adobe. There is no law that says that standards must be adhered to. It would seem that in this case Samsung has not followed the Adobe standard properly.