Short answer: never. No real bank, police officer or regulator will ever ask you to share your phone screen, and anyone who does is trying to watch you log in.
It begins with a phone call you weren't expecting. The caller says they're from your bank, the police or the Financial Conduct Authority, and they tell you there is suspicious activity on your account or fraudulent payments that need to be stopped right now. Some claim your phone has a virus instead.
The goal of that first call is panic. When you're worried about losing money, you're far more likely to follow instructions without stopping to check who you're actually talking to.
Next, the caller asks you to move to a WhatsApp or FaceTime video call so they can "help fix the problem." Then they walk you through turning on screen sharing, which only takes a few taps. It feels like tech support. It isn't.
Once your screen is shared, they can see almost everything on your phone, including the one-time codes your bank sends by text or notification to approve payments and logins. With those codes, they can move your money or buy things in your name while you're still on the call.
In one case reported in the UK, a man was kept on calls by fake FCA inspectors for about 20 hours over three days. They took more than £27,000, including six iPhone and iPad purchases.
The rule is simple enough to share with your parents today: if anyone calls you and asks to see your screen, it's a scam, every single time.
Source: Which?: The WhatsApp screen-sharing scam that could drain your bank account
This is one trick out of dozens. The Scam-Proof Playbook covers bank impersonation calls, WhatsApp scams, AI voice cloning, and more, in plain language, with real examples.