What's wrong with your phone?

Start from what the phone is doing to find out what is probably broken, what to do right away, and what the repair costs.

• Broken screen: what to do and what it costs

  Cracked glass, a black picture or touch that doesn't respond — in most cases the fix is a full display replacement. But it isn't always the display. Here is how to tell, what to do right away, and what price to expect.

• Phone battery drains fast, overheats or shuts down: the usual causes

  The phone doesn't last the day, the percentage drops in jumps, or it switches off at 30%. Most often a worn battery is behind it — but not always. Here is how to tell, when it's dangerous and what price to expect.

• Swollen battery: how to spot it and why it can't wait

  The back cover is lifting, the display is separating from the frame, or the phone rocks on a flat table. That isn't a drop or bad glue — it's a battery that is swelling. Here is how to recognise it, what to do right away, and what price to expect.

• Phone won't charge: port or battery? How to tell

  The cable has to sit just right, the percentage won't move, or the phone only ever gets half full. Most of the time it's a worn charging port — sometimes the battery. Here is how to tell the two apart at home in five minutes, what to do right away, and what price to expect.

• Phone fell in water: what to do right away and what can be repaired

  The phone ended up in the sink or the pool, or got soaked in the rain. The first few hours matter more than you'd expect — the right steps save both the board and your data. Here is what to do right away, how to tell what the water damaged, and what price to expect.

• Can't hear calls or they can't hear you: earpiece, speaker or microphone

  The other person sounds faint, the loudspeaker doesn't play, or people can't hear you on calls. Each of these has a different cause and a different repair — and sometimes turning off Bluetooth or cleaning a grille is enough. Here is how to tell them apart, what to try at home and what price to expect.

• Screen not responding to touch, flickering or showing a green line: what to do

  The phone taps on its own, part of the screen doesn't respond, the picture flickers or a green or pink line runs across it. Sometimes removing the screen protector or unplugging the charger is enough; other times the panel is damaged. Here is how to tell, what to do right away and what price to expect.