OS X allows multiple accounts to be logged in on a single Mac at the same time. You can lock a user’s account, switch to another one, and come back to the first one to find all your apps and windows untouched. The functionality is all there, but it takes an unnecessary number of clicks to get to it. Unless you have an app that triggers it, OS X can’t be locked with a keyboard shortcut; the easiest way to access the ‘Lock Screen’ option is by enabling Keychain’s icon to appear in the Menu Bar. In that case, it takes two clicks to lock your screen. If you want the Switch User screen to appear instead of your own user profile already selected and ready to log in, you have to click the ‘Switch User’ option at the bottom of your lock screen. For something so simple and frequently used, this is a lot of clicks. MacLoc is a free Mac App that make it slightly easier; it locks your screen and switches to the ‘Switch User’ option for you so that you don’t have to do it yourself.
Once installed, MacLoc adds its padlock icon to the Menu Bar. Click it and select ‘Lock’ to lock your screen, and your Mac will be locked, taking you directly to the Switch User screen. It really is this simple.
MacLoc adds a lot of convenience in locking your screen, but the lack of a keyboard shortcut can be a significant limitation to many. MacLoc reduces the effort you would normally have to make to lock your screen and leave it on the ‘Switch User’ screen, but the app can do better than that. There should be an option to trigger the ‘Lock’ function by simply clicking the app’s icon, or using a keyboard shortcut.
The ‘Switch User’ screen appears immediately after locking your screen only if you use MacLoc to lock it. If you lock the screen normally instead, you will still see the log in screen for your own user only. It could also be really useful if MacLoc were to just run in the background and ensure that the system would always shows the ‘Switch User’ screen no matter how the screen was locked.
MacLoc has no preferences to manage, and it does not add any sort of additional security or protection to your system. Some apps that allow you to lock your Mac add an extra layer of security by enabling their own password to be set, but MacLoc is quite straight forward, and is meant more for convenience than for security. The app is bound to be most useful on a Mac shared by two or more users.