App Passcode & Biometric Security | USDT Express

A crypto wallet and a bank account both live inside your USDT Express app, which is exactly why the app ships with its own passcode and biometric lock, separate from your account password. Setting it up takes under a minute and adds a real layer of protection if your phone is ever lost, unlocked, or picked up by someone else.

Why an app-level lock matters

Your account password protects your USDT Express login, but once you're logged in on a phone, the app usually stays signed in for convenience. Without an app-level lock, anyone who picks up your unlocked phone could open the app and see your wallet balance, sell history, or even attempt actions. A dedicated passcode — plus fingerprint or Face ID — means the app itself asks for verification every time it's opened, independent of whether your phone is unlocked.

This matters more for a platform like USDT Express than for a typical app, because the app shows real INR balances, bank withdrawal history, and personal deposit addresses. Treat it the way you'd treat a banking app, not a social media app.

Setting up your passcode

Setting up the passcode takes place entirely in Settings:

1. Open the USDT Express app and go to Settings.
2. Tap App Lock (sometimes labelled Passcode & Biometrics).
3. Choose a 4- or 6-digit passcode — avoid obvious patterns like birthdays or repeated digits.
4. Confirm the passcode by entering it a second time.
5. Once set, the app will ask for this passcode every time it's opened or returns from the background after a period of inactivity.

If you ever forget your passcode, you can reset it through account verification, similar to a password reset — it won't lock you out permanently, but it does require re-confirming your identity, which is by design.

Turning on fingerprint or Face ID

Once a passcode is set, biometric unlock becomes available as a faster alternative:

• On Android, tap Enable Fingerprint Unlock in the same App Lock menu and follow your device's fingerprint prompt.
• On iOS, tap Enable Face ID and confirm with Face ID when prompted.
• Biometric unlock always falls back to your passcode if the biometric scan fails or isn't recognized, so you're never locked out because of a scanning issue.

This is the same passcode you'll rely on when scanning a QR code to submit a transaction hash inside the mobile app, so setting it up early makes every later sell smoother too.

Biometric lock doesn't replace the passcode — it sits on top of it as a convenience, while the passcode remains the fallback method and the one used for higher-risk actions.

What passcode and biometric lock actually protect

Layer	Protects against	Where it applies
Account password	Someone logging into your account from a new device	Login screen, new device/browser
App passcode	Someone opening the app on your already-logged-in phone	Every app open, after inactivity
Fingerprint / Face ID	Same as passcode, faster and harder to observe/shoulder-surf	App open, optional for sensitive actions
Device/session list	Unknown devices staying logged in	Settings, reviewed manually

Combined with a device and session list you check periodically, these layers make it very unlikely that anyone but you can act on your account, even if your phone is briefly out of your hands.

Best practices beyond the basics

A few habits worth adopting alongside app lock:

• Don't reuse your phone's unlock PIN as your app passcode — if one is compromised, you don't want both to be.
• Review your device list in Settings occasionally and log out of anything you don't recognize.
• Keep your phone's operating system updated, since biometric security depends on the underlying OS staying patched.
• Pair app lock with the other habits in our account security tips, especially reviewing your device list and avoiding phishing links.
• If you sell a phone or hand it down, always log out of the USDT Express app first, not just clear the passcode.

Frequently asked questions

Q: What happens if I fail Face ID or fingerprint too many times? The app automatically falls back to asking for your passcode, so you're never permanently locked out by a biometric mismatch.

Q: Does app passcode replace my account password? No, they serve different purposes — your password secures login on any device, while the app passcode and biometrics secure the app on a device where you're already logged in.

Q: Can I turn off the app lock if I don't want it? You can disable it in Settings, but given that your INR wallet and withdrawal history are visible in the app, we strongly recommend keeping at least the passcode active.

Setting up app passcode and biometric lock is one of the fastest security upgrades you can make on USDT Express. Sell USDT now once it's enabled, and browse more tips in our account security guide.