Samsung devices don't support Adoptable Storage. However, there is a workaround with ADB (root not required). Here are the commands for ADB: adb shell sm list-disks sm partition <DISK> private reboot >**Notes:** > 1. `<DISK>` needs to be replaced with the output of the previous command. For example `sm partition disk:179,64 private`. > 2. If you don't want to convert the whole disk, then use this command instead: `sm partition <DISK> mixed <VALUE>`, where <VALUE> is the percentage (0-100) to keep as external storage. For example `sm partition disk:179,64 mixed 50` for 50%. > 3. Reboot is optional, but recommend, so all apps detect the external storage. <hr/> If you have root access, you can use my app [Root Essentials][1] instead. It can do all of this automatically without a PC or terminal commands. [1]: https://play.google.com/store/apps/details?id=com.superthomaslab.rootessentials