APK files allow Android applications to be installed outside the standard app-store process. That can be useful, but it also means users should pay attention to where a file comes from and what it does.
There is no simple label that can guarantee every APK is safe.
Check the Source
Download files only from sources you have a reason to trust. Be careful with websites that use misleading download buttons, unexpected redirects, or files that do not match the application you intended to install.
Check the File
Before installing an APK, check its name, version, package information where available, and file size. An unusual filename or unexpected application identity should be treated carefully.
Review Permissions
Pay attention to permissions requested by an application.
For example, an app that requests access unrelated to its normal function deserves additional scrutiny.
Keep Android Protected
Keep your Android operating system and security features updated. If your device displays a security warning about an application, don’t ignore it without understanding why the warning appeared.
Google also notes that downloadable applications can fall under unwanted-software concerns when they behave deceptively, unexpectedly, or negatively affect a user’s browsing or computing experience.
Avoid Modified Files From Unknown Sources
Modified APKs can change an application’s behavior. If you don’t know who modified a file or what was changed, there is an additional risk compared with a verified original application.
Protect Your Accounts
Never give your passwords, OTP codes, recovery codes, or other private credentials to an unknown person claiming to help with an APK or game.