Most guides to improving your phone signal advise you to buy a signal booster – expensive gadgets which also have the drawback of being illegal in the UK.

But if you find that your calls keep cutting out, there ARE a few things you can do, beyond simply switching to calls via Wi-Fi, or going outdoors.
Here’s a few simple steps you can take – without paying out.
Turn your phone to Flight Mode, then back again
Sometimes, the problem you’re having is that your phone is ‘holding on’ to a weak signal from a mast.
If you turn your phone to Flight Mode (quicker than turning off), then back on, it will connect to a fresh mast.
Go upstairs
It’s all about getting a clean ‘line of sight’ to the mast – which you’re more likely to do if there’s less stuff in the way.
Simply going upstairs can work, especially in country areas.
Use a Bluetooth wireless headset – and ditch your phone case
If you’re having trouble connecting, your hand could be getting in the way of the aerial on older iPhones.
To keep things clear, try leaving the phone somewhere you KNOW you get good reception, then speaking via a wireless headset.
Check your home for ‘blackspots’
Mobile signal can often be blocked by walls (yours or other people’s) and other obstacles – meaning your house has black spots.
Find out where yours are by using this guide that will tell you exactly how much signal you have on your iPhone.
Open a window
Simply opening a window can offer a boost to your mobile signal.

Some ‘insulating’ panes in particular can interfere with mobile signals.
… and if all else fails, switch to wifi and use apps like Whatsapp, Skype or Apple’s own wifi calling service available from networks such as EE.(from metro.co.uk)