Think you know your smartphone inside out? Think again.
Whether you own an Android or iOS device, there are plenty of hidden features - also known as Easter Eggs - to discover.

Let's get started. Grab your phone and keep on reading to discover everything from built-in games to a secret octopus.

Android Easter Eggs

One Easter Egg every Android user can find, no matter which version they use, can be found in Settings. Just head there, locate 'About Device' or 'About Phone' (sometimes this is in 'Software Info') and tap to open. Scroll to find Android Version and then quickly tap it four to five times.

Depending on your version of Android, the surprise that appears will be different. If you're using the latest version, Android Oreo, an O will appear. Simply tap it five times and an octopus will suddenly float around your screen. Android Nougat users, meanwhile, will unlock the Android Neko cat-collecting game by tapping on the N five times.

The Chrome browser, both on your smartphone and on a desktop, has its own secrets too. One Easter Egg involves a rather friendly dinosaur, which you'll if you're unable to connect to the internet. Tap the dinosaur and it'll start running. Simply use the 'up' arrow to jump over obstacles and the 'down' arrow to duck.

Still on an Egg hunt? Activate Google Assistant by saying 'OK Google' and get ready for some Harry Potter-themed fun. Just say 'Lumos' and your device's flashlight will magically turn on - just like a Hogwarts spell. Ready to switch it off? Simply say, 'Nox' (imaginary wand-swishing optional).

iOS Easter Eggs

When it comes to iOS Easter eggs, the focus is firmly around Siri. Apple's personal assistant has plenty of witty answers to unleash - you just have to ask the right questions. Some of our favourites include sneakily saying 'Hey Siri. OK Google' to which you'll receive a sarcastic response. You could also ask 'Hey Siri, why are fire trucks red?', but don't expect a succinct answer.

Finally, try asking 'Hey Siri. Do you have a boyfriend?' - a question which has multiple answers, but our favourite has to be 'No, but drones are always trying to pick me up'.

Apple have hidden some other, subtle Easter Eggs too. Did you know the writing on the book emoji isn't made up of squiggly lines? If you zoom in, you'll realise it's actually text from an old Apple campaign titled Think Differently - it begins by saying 'Here's to the crazy ones. The misfits. The rebels.' The icon for Maps also holds a secret. The street and pin you can see reveal the location of Apple campus on the 280 freeway.

Apple tend to create 'limited edition' style Easter Eggs too, around special events. One of the latest was released last Christmas, in December 2017. If users went to the Apple Store on their iPhone and typed 'Let It Snow' into the search bar, snow would begin to fall from the top of the screen.

Google Easter Eggs

Open up your browser, head to Google and get ready for hours of fun. There are many Easter Eggs - which can be enjoyed on both your smartphone or desktop - built into the search engine.

The first involves hidden games. If you're ever bored, type 'solitaire', 'tic tac toe', 'play dreidel' or even 'fidget spinner' into the search bar. The games will appear where the first few search results usually sit, and you can play to your heart's content. Typing 'Pacman' brings up a Google Doodle from 2010, which lets you enjoy your favourite arcade game no matter where you are.

Fancy going back in time, to see what Google looked like in the late nineties? Search for 'Google in 1998' to see just that.

There are hundreds of Easter Eggs waiting to be unearthed with your smartphone. Get hunting, and see how many you can find.

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