Mobile Guideline: Lost Devices, Infection Checks & Recovery
Smartphones contain our entire lives, making them prime targets for thieves and scammers. This guide covers what to do if your Android or iPhone is lost, stolen, or behaving suspiciously.
Key Topics:
- Lost/Stolen: Using "Find My", avoiding the fake Apple/Google SMS scam, and blocking your IMEI.
- Infection Check: How to check Android vs iOS (they handle security very differently).
- Recovery: Securing accounts, replacing SIM cards, and avoiding "The Backup Trap".
Click "1. Lost or Stolen" in the top menu to begin.
Step 1: Lost or Stolen Device
Act quickly to locate or wipe your device to protect your personal data.
⚠️ CRITICAL WARNING: The "SMS" Scam
If your phone is stolen, you may receive an SMS or Email on your backup phone a few days later saying: "Apple/Google has found your device. Click here to view location."
DO NOT CLICK. This is a sophisticated phishing scam by the thief to steal your password so they can unlock the phone for resale. Only trust the official websites listed below.
1. Locate & Lock (Official Sites Only)
- iPhone/iPad: Go to icloud.com/find from any computer. Mark as "Lost".
- Android: Go to android.com/find. Select "Secure Device".
2. Report to HK Police & Carrier (Block IMEI)
If stolen in Hong Kong, file a report for insurance. When you call your carrier, ask them to "Block the IMEI". This prevents the physical phone from ever connecting to a cellular network again, making it useless to the thief.
*Note: Phone numbers below may change. Please check official carrier websites for updated numbers.
- HK Police: Call 2860-2000 or use the e-Report Centre.
- Carriers (Call to suspend SIM & Block IMEI):
- CSL/1O1O: 2512 3123
- China Mobile HK: 2945 8888
- SmarTone: 2880 2688
- 3 Hong Kong: 1033
Step 2: Signs of Infection
Phones behave differently than computers. Know what to look for based on your operating system.
Common Symptoms (Both iOS & Android)
- Battery/Heat: Phone gets extremely hot or the battery dies rapidly while doing nothing in your pocket.
- Data Spikes: Large, unexplained data usage from unknown apps.
- Pop-ups: Aggressive ads appearing on your home screen or lock screen.
How to Check Your Device
🤖 For Android Users
Android is more open, so malicious apps can occasionally slip through.
- Run a Scan: Go to the Google Play Store > Profile Icon > Play Protect > Scan.
- Check Admin Apps: Go to Settings > Security > Device Admin Apps. Uncheck anything suspicious.
- Check Accessibility Services (Crucial): Malware often disguises itself as a normal app and abuses accessibility features (meant for the visually impaired) to secretly control your screen. Go to Settings > Accessibility > Downloaded Apps. If an app you don't recognize has permission here, turn it off and delete the app immediately.
🍎 For iPhone (iOS) Users
Why iPhones can't run Antivirus: Apple uses "Sandboxing," meaning apps are strictly isolated and cannot look at what other apps are doing. Therefore, a true Antivirus scan is impossible on an iPhone. If an App Store app claims to "scan for viruses," it is misleading.
Do this instead:
- Check Profiles (Important): Malicious apps often bypass security by installing a "Profile". Go to Settings > General > VPN & Device Management. If you see a "Profile" or "Configuration" you don't recognize, delete it immediately.
- Fix Calendar Spam: If your calendar says "VIRUS DETECTED," it is not a virus. You accidentally subscribed to a spam calendar. Go to the Calendar App > Calendars (at the bottom) > Uncheck or Delete the weird calendar.
- Use Safety Check: If you suspect someone (like a stalker) is tracking your iPhone, go to Settings > Privacy & Security > Safety Check. Use "Emergency Reset" to instantly stop sharing your location and revoke privacy permissions for all apps.
Step 3: Recovery & Prevention
If you confirmed a hack, lost your device, or want to prevent future disasters, follow these steps.
1. Prevention: Stolen Device Protection (iPhone)
Thieves in public places often watch you type your PIN, steal the phone, and immediately change your Apple ID password to lock you out forever. You must turn on Apple's defense against this.
Action: Before your phone is stolen, go to Settings > Face ID & Passcode > Stolen Device Protection and turn it ON. If a thief steals your phone and knows your PIN, this feature requires your actual Face or Fingerprint to change your Apple ID password if you are away from home.
⚠️ The 2FA "SIM Card" Problem
If your stolen phone was the only way you received SMS login codes (OTPs), you cannot log into your Email or Banking to change your passwords.
Action: Go to a physical mobile carrier store (CSL, SmarTone, etc.) immediately with your ID to get a Replacement SIM Card. Put it in an old backup phone so you can start receiving your SMS codes again to secure your accounts.
2. Android: Safe Mode
If your Android is acting crazy (crashing or spamming ads), boot into Safe Mode (Usually by holding the Power button, then long-pressing the "Power Off" icon on the screen). If the problem stops in Safe Mode, you know a recently installed third-party app is the cause. Uninstall recent apps.
3. Factory Reset & "The Backup Trap"
If you cannot remove the malware or the device was stolen and recovered, you must Factory Reset it.
- Android: Settings > System > Reset options > Erase all data.
- iOS: Settings > General > Transfer or Reset > Erase All Content.
Warning: The Backup Trap!
If you factory reset an infected Android phone, DO NOT choose "Restore all apps" from your Google backup when setting it up again, or you will accidentally reinstall the virus. Only restore your contacts, photos, and messages. You must re-download your apps manually from the Play Store.
📝 Knowledge Quiz
Test your mobile security knowledge. Click the correct option.