We can change the order of apps appear in app menu as desired. These apps are displayed in drop down (Top Right) list of every application page. User can see the apps based on the visibility setting and user permissions. Administrator will see all the apps created in salesforce or installed through app exchange but other users will see the apps based on visibility.
Setup > Manage Apps > App Menu
Apps can be reordered by using the Up/Down arrows.
Hide all standard and custom apps in the App Launcher: When enabled only approved connected apps appear in the user’s App Launcher.