If you have a Samsung phone you can try something similar now called secure folder. Search in your options to create. Then you can install apps in there and all the apps and data are sandboxed from the rest of your phone. You can't access the data from the main phone and apps in the secure folder don't have access to your main phone.

I have one setup for my banking app and other apps I would prefer to be private. Have to enter a password to get access to that area and it is encrypted when locked. It works real well.