Ok so this is my desired use case: I have a ~600GB folder of music tracked by my btsync desktop (potentially fully by another server but not yet at this time) What I would like to do, is be able to selectively dowload or remove portions (~40 GB or so) of this music to my ext sdcard on my Galaxy S4 depending on my whims of what I feel like listening to at the time. I've created a read only sync from the device, disabled autosync, and it appears that I can accomplish this basically. I'm trying to understand why exactly ALL of the folders are copied over to device (and displayed in the ON DEVICE tab). This is a complete headache to manage, because there is no way to tell which folders' files are actually copied to the device unless you just remember or browse down into each folder. I have well over 8000 folders + sub folders, so this is completely untenable. I desire for simply all folders to be shown only in the ALL FILES tab, and the ON DEVICE tab to only show folders that contain files that are... actually on the device. I honestly consider this to be a bug because I can't think of a rationale why you would want 1000s of empty unsynced folders copied to your device. Additional desired features in the android app that aren't nearly as critical at this time, but would be great down the road: 1. The ability to track exactly which sub folders are synced to my phone, and add/remove it remotely from the web client. Perhaps this is already possible in the windows/mac client, I don't know, but it is not currently in the linux web client which I am using. Obviously this could be done by instead just choosing which folders to sync, but this is very cumbersome, requires you to copy a secret or scan a QR for each and every album, and would not allow you to manage it from the device client itself. 2. The ability to search and filter the cached file/folder list from the android app. Filters would also allow me to say, filter out all album folders that have the year "2008" in their name and select just those to sync, or sync all folders from the 70s by querying "197*". Or jump quickly from say "Fugazi" to "T. Rex" without scrolling down a few thousand folders. wildcard character support in the search would be nice too... 3. Multi-select in the android app - An android standard nowadays, long press to start multiselect, select a bunch of folders, and then sync them all to the device in one action. Delete them in the same manner from the on device tab. All and all I think btsync has tons of potential, but it may be a bit premature for anything other than full backups of folders from server to server imo.