A phone that warms up is normal. A phone that is too hot to hold, or that shuts down or dims its screen, is telling you something. Heat also wears out batteries faster, so it is worth fixing.

When warm is normal

• While charging, especially with a fast charger.
• During gaming, video calls, camera and navigation.
• Right after a big update or restore, when the phone is busy in the background.

Common causes

1. Charging while using it. Playing a game on the charger adds heat from two sources.
2. Direct sun or a hot car. The phone cannot cool itself.
3. A thick or insulating case. It traps heat, especially when charging.
4. A heavy app or a stuck one. An app running at full load in the background.
5. Weak signal. The phone works harder to hold a connection.
6. An old or worn battery. See how to check your battery health.
7. A bad charger or cable. Use the one that came with the phone or a good brand.

How to cool it down

1. Stop what you are doing and close the heavy apps.
2. Unplug the charger and take off the case.
3. Move it to the shade. Let it cool slowly in a cool place.
4. Switch on flight mode for a few minutes if signal is weak.
5. Restart the phone.

What not to do

• Do not put it in the fridge or freezer. Sudden cold can cause condensation inside.
• Do not use a cooling spray or a wet cloth.
• Do not keep charging a hot phone.

Prevent it

• Keep software and apps updated.
• Lower the screen brightness and the graphics setting in games.
• Charge in a cool, open place and avoid charging under a pillow.
• See the charging myths, sorted and do you need a case.

When to get it checked

Get it looked at if the phone is hot even when idle, the battery swells or the back lifts, it shuts down on its own, or it gets hot within minutes of charging. A swollen battery is dangerous. Stop using the phone and take it to an authorised service centre. If the phone is just slow, see how to speed up a slow phone.