People searching for iPhone app lock usually have a simple need: the phone is already unlocked, but certain apps should not be opened by someone else.
Chat and social apps are the first group to protect. Messages, email, social networks, and work communication tools often contain private relationships, file previews, recent contacts, and sensitive notifications.
Photos, files, and cloud drives are another high-risk group. A person may only need to view one image, but a quick swipe can reveal nearby screenshots, documents, or private media.
Work apps also deserve their own boundary. Project tools, client conversations, meeting notes, and internal documents do not belong in casual shared-use moments.
The best app-lock setup does not lock everything. It protects the apps another person does not need to open. iPhone Locker is built around groups and shared-use scenarios, so users can protect the right entry points before lending their phone.