Software

[27RRM]

add secure folder, knox software, app lock to samsung m31 and also timely update software.

[rock1232]

secure folder can't be added because knox security( hardware )is needed which your devices lacks.
for more information tap on link given below:-
https://r2.community.samsung.com/t5/Galaxy-M/secure-folder-based-on-knox-security-hardware/td-p/6060...

[Badshahokay]

please add secure folder application in m21 i need secure folder for my device m21