The built-in Locker app that comes on BlackBerry smartphones these days is an excellent app for tucking away sensitive user data such as photos, apps, downloaded files, and more and securing them behind a password and fingerprint.
That said, some folks like to take it one step further and hide the Locker app itself, which the app settings allow you to do, but before you hide the app, there's one crucial step you should take, and that's setting up a keyboard shortcut to launch Locker.
The reason being, once you hide the Locker app unless you have a keyboard shortcut set up, there will be no way to launch Locker. The icon disappears, and the app is no longer listed in the apps list, making it nearly impossible to start. That is, of course, great if you're looking to hide the app but not so great if you're looking to ever return to it.
Before you set Locker to be hidden, it does warn you that this will be the case, but it doesn't explicitly forcefully tell you that need you to set a shortcut and it really, really should because it's not entirely clear how to regain access should you not be able to find the icon, nor be able to launch Locker through traditional means.
With that covered, should you find yourself in the predicament where you did not create a shortcut for Locker, can no longer find the icon and are not able to launch it, there is a way you can 'trick' Locker to launch as highlighted by DanylW in the CrackBerry Forums.
That process will force Locker to launch and you'll once again have access to all your files in Locker, but more importantly, it will allow you to temporarily unhide the app, create a shortcut and then allow you to hide it again versus having to wipe your device, and losing your files to get everything back to normal. A simple re-wording of the warning message in Locker before you hide it would go along way in preventing this but since it's not in place yet, at least there's a process to prevent it and retrieve the files.