What's the best Android app for preventing others from accessing private photos on my phone?

App Lock is a strong contender for users seeking to guard personal media. The app operates by placing a lock directly on the phone's gallery or photo applications, requiring a fingerprint, PIN, or pattern to open them. This approach is effective for scenarios like sharing a device with family or preventing casual snooping. A key feature is the ability to create custom recovery questions, offering a backup access method if the primary unlock is forgotten. Reviews indicate users appreciate this specific function for securing personal photos and videos. The app also includes a break-in alert feature, which captures a photo of anyone who fails an unlock attempt, adding a deterrent layer. However, a significant limitation exists: if the App Lock application itself is uninstalled, all protections are removed. This means determined individuals with physical access to the device could bypass the locks entirely. Furthermore, while it locks apps, it does not currently support locking specific folders within the file system, a feature some competitors offer. For straightforward app-level security, including photo galleries, App Lock provides reliable and customizable options, though its effectiveness is contingent on the app remaining installed on the device.