A driver is generally only allowed to use a mobile phone while driving if it is fully hands‑free (e.g., mounted and voice‑controlled) or in a genuine emergency where stopping is unsafe. Laws vary by country and state, but the pattern is very similar worldwide.

✅ When mobile phone use is usually allowed

In most modern traffic laws, a driver can legally use a phone while driving only in these limited situations :

  1. Hands‑free use only
    • Phone is in a fixed cradle/mount or connected via Bluetooth.
    • You use:
      • Voice commands (e.g., to start a call or navigation).
      • Steering‑wheel or single‑button controls.
      • Speakerphone without holding the device.
    • You do not hold, tap repeatedly, type, scroll, or look at the screen for long.
  1. Emergency calls while moving
    • Calling the emergency number (e.g., 999, 112, 911) to report:
      • A serious crash.
      • Fire.
      • Medical emergency.
      • Dangerous, reckless, or impaired driver.
    • Allowed to briefly hold the phone only if it is unsafe or impractical to stop first.
  1. When the vehicle is safely parked
    • The car is:
      • Fully stopped.
      • Safely parked off the active roadway (not just at lights or in traffic).
    • Engine may be on or off depending on the jurisdiction, but you must not be in active driving flow.
  1. Contactless payment while stationary
    • Paying at a drive‑through or toll while:
      • The vehicle is stopped.
      • You briefly handle the phone for payment only.
  1. Remote parking features
    • Using the phone as a remote control to park the vehicle, where this is explicitly allowed and the vehicle is not being driven normally on the road.

❌ When a driver must NOT use a phone

Across many regions (UK, US states, Canada, Australia, etc.), it is illegal to hold or actively use a mobile phone while driving for things like:

  • Calling or answering while holding the phone.
  • Texting, messaging, or emailing.
  • Browsing the internet or social media.
  • Taking photos or videos.
  • Watching videos or playing games.
  • Manually entering navigation while moving.
  • Holding the phone at traffic lights or in a traffic jam.
  • Using it even in offline/flight mode if you’re holding and interacting with it.

For commercial drivers (e.g., trucks, buses), the rules are often stricter : using a hand‑held device can carry heavy fines, license penalties, and even disqualification, and even dialing more than one button can be illegal.

Why the rules are so strict

  • Even a few seconds of looking at your phone means you travel a long distance “blind” (at about 55 mph you can cover the length of a football field in under 4 seconds). This massively increases crash risk.
  • Texting or complex conversations reduce attention and slow reaction time, making it harder to respond to hazards, especially in heavy traffic, at night, or in bad weather.

A good practical rule:

If you wouldn’t feel safe doing it with a police car beside you, don’t do it with your phone while driving.

Quick checklist for drivers

A driver can safely and typically legally use a mobile phone while driving only if :

  • It is hands‑free (mounted/Bluetooth, voice‑controlled, no holding).
  • Or it’s a genuine emergency and stopping first is unsafe.
  • Or the car is properly parked and out of live traffic.
  • Or you are briefly paying at a drive‑through while stationary.

For precise legal details, a driver should always check the current road rules in their own country or state, as penalties and exact wording differ by jurisdiction.

TL;DR:
A driver may only use a mobile phone while driving if it is hands‑free or for a genuine emergency when stopping is unsafe; anything involving holding, typing, or scrolling is usually illegal and very dangerous.

Information gathered from public forums or data available on the internet and portrayed here.