I did the research upon this actually our devices have 64 bit os installed in every flagship device from s8 to latest note 10 plus and note 10 and the app called s secure is made up of 32 bits so samsung made the mid range and mid premium devices with 32 plus 64 bit support our devices does not support the inbuilt app due to the 32 bit factor of s secure app . that's why we dont get to see applock as well as I wanted the s bike mode in my device as well but Samsung isn't made the compatibility of these app lock and s bike mode due to the 32 but factor.
our flagship devices only support 64 bit apps .
so it is hard for samsung make the app compatible unless it is a marketing strategy for not providing these apps Samsung isn't giving the full access to all the apps and features which a device is compatible
