SD card change to default write disk.

I think we have the same tablet..mine's an RCA 16gb running 5.0.1 OS (Lollipop) I have not been able to switch apps to as card even after setting the default write disk to SD card..best I can do is move pics and music. Best way to tell is settings>apps click on an app preferably one that aasumedly would easily switch to SD card. If there's nothing like an option to move it to external storage..forget it..I know my tablet is three or four years old. I got one each for wife and me for Xmas half price off 80.00 for both. This maybe a reason apps aren't moveable...cheap price..sorry hun..maybe someone else knows something I dont...