Use battery-saver modes
Many manufacturers include battery-saving modes as standard on their devices, which can automatically turn off features and limit screen brightness once the battery reaches critical levels. They're great for stretching 10 per cent battery out over an hour or more.
There are also extreme battery saver modes, which are even more drastic. These often limit you to just a handful of apps, or even convert the display to greyscale. If you're in really dire circumstances, they can extend a phone's lifespan considerably.
Charge regularly
Of course, one cast-iron way to make sure your phone doesn't die before the end of the day is to regularly charge it. Getting into the habit of plugging your device in when you get home or while your sat at your desk ensures it won't die at a critical moment.
Keeping a portable power bank with you while you're out and about can also help. There's a wealth of cheaply-available options to be had, all of which can be slung in a bag or pocket in case you need a top-up.
