A calculator vault app is a privacy app disguised as an ordinary calculator. It performs real math, but entering a secret passcode reveals a hidden vault for private photos, videos, contacts and locked apps. LockApps is a free example.
How the calculator disguise works
- Open LockApps — it shows a normal, fully functional calculator.
- Type your secret passcode using the number keys.
- Press = to open the private vault.
To anyone else, it's just a calculator. There's no obvious "unlock" button — the passcode-and-equals gesture is the only way in.
What's inside the vault
- App Lock behind Face ID
- App hiding from the Home Screen
- A private photo and video vault
- Private contacts and parental controls
You can even disguise the app's Home Screen name and icon so it appears as "Calculator" or "Notes".
Are calculator vaults safe?
A good one stores everything encrypted on-device with no account. See are calculator vault apps safe? for what to check.