Here's what the small hole on the back of your iPhone is for. Photo / Getty Images
Apple has steadily packed its iPhones full of more and more exciting features over the years.
But there are loads of innovations you've probably never noticed, including a small hole just next to the camera, reports The Sun.
So what on Earth is this tiny indentation for?
Well, it's actually just a small microphone designed to capture sound coming from the direction the lens is pointing.
It was first introduced in the iPhone 5S, Metro reports.
The iPhone now has this microphone as well as ones on the top and bottom.
This means it can pick up sound no matter how an iPhone owner is holding their gadget.
When he first announced the three microphones, Apple's Phil Schiller said: "We now have not two but three microphones.
"This helps in Facetime calls, in videos, we can use them for noise cancellation, and we can use them for applications like Siri."
Here are five other features you might not know exist on your iPhone.
Take photos with your headphones
If tapping the phone to take your photos is leaving you with blurry pics, this may help.
Plug in your headphones and click the volume buttons to start snapping away without touching the screen.
Use the built-in spirit level
Many people have no idea that their phone has an accurate spirit level hidden in an app nobody uses.
Open the Compass app and swipe left to start levelling.
Get an accurate signal reading
If you're struggling for signal then you can change your settings to temporarily show you a signal reading in numbers rather than bars.
Dial *3001#12345#* on your iPhone then press Call to enter Field Test mode.
In the top left of your screen you'll see a number between 0 and -100, which represents your exact signal strength, with zero meaning perfect signal and -100 indicating terrible signal.
In this mode, you can watch the number change as you walk around to find the exact spots where the signal is strongest.
To exit Field Test mode just press the home button and you're back to normal.
Turn off red bubbles
Having a homepage full of notification bubbles is seriously annoying.
Go to Settings>Notifications to turn off the red bubbles, called Badge Icons, for good.
Generate random passwords
The safest passwords are generated at random, making them almost impossible for hackers to guess.
Ask Siri to generate a random password next time you make a new account: you can even specify how many characters you want.
• This story first appeared on The Sun.
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