I?ve tried on several different phones now, a OnePlus One, a OnePlus 7 Pro, a Nexus 6P, (and possibly one other which I can?t recall right now?). The OPO and Nexus are running the latest supported LineageOS. The OnePlus 7 Pro had the latest stock Android 10 (I no longer have that phone). They all could host USB flash drive images, but that is only useful sometimes. I have to grab a computer and convert an existing ISO into a flash drive image. This is somewhat time consuming. Sometimes I don?t bring a laptop with me, and I just want to download the latest version of XYZ bootable ISO, and host it from Drive Droid without spending a bunch of time converting it. Drive droid seems to think that the kernels for the respective phones don?t support USB CDROM. I?m starting to wonder the same thing.