(Pocket-lint) - There's always a bit of a learning curve when it comes to mastering new apps and WhatsApp is no different. It's wickedly popular (it recently hit two billion users) and extremely easy to get started using right away, but it does have a few quirks that aren't immediately obvious at first. There are also a few hidden features that aren't the simplest to enable.

If you're already familiar with the basics, then check out our guide to the secret WhatsApp tips and tricks you might not know about.

We've gone over everything you could possibly want to know about WhatsApp to get started right here. 

What is WhatsApp and how does it work?

WhatsApp is an instant messaging app that Facebook acquired in 2014. The app is available for iPhone and Android devices as well as a desktop app for Windows and macOS. It's also available on the web in any browser. 

It works alongside your phone contacts. If somebody's in your contacts, you can communicate with them. Once installed, you'll be asked to enter your mobile phone number - it essentially works off that, so it's always tied to your phone number. 

First and foremost, WhatsApp is a chat app. You'd typically use it to send things like text messages, images, video and even documents. It works over the internet, so it will use your data allowance if you're not on Wi-Fi. 

You can message people individually or you can create groups - and it's this that people find most useful, despite rivals such as Apple's Messages and Facebook's own Messenger being able to do the same thing. 

But increasingly it's being used for voice calls and, more recently, video calls, too. You can now video call up to eight people. 

Currently, WhatsApp has no adverts (we believe this will change in future) and it is now entirely free after a scrap of the yearly subscription charge that was in place a few years ago. 

WhatsApp messages and calls are end-to-end encrypted for security. All messages, photos, video, files, and calls are completely secure - only the sender and receiver of any message will be able to see the contents. Even WhatsApp can't have access to the message's contents. You can also protect the app with a PIN (known as two-step verification). 

How to use WhatsApp

WhatsApp has a menu bar that runs along the bottom of all the screens within the app. It has the following five tabs: Status, Calls, Camera, Chats, and Settings. Tap on any tab in order to access a new screen and its related features and settings.

Status is a bit useless really and enables you to choose a Status to show to contacts. It could be - "I'm in meetings all day" or "Only chat, don't call". That kind of thing. In reality, few people use this. 

Calls shows you your recent call list for both voice and video - all your placed and missed WhatsApp calls

Chats is the key tab. This is a running log of all your active messages. Tap the draft symbol in the upper right-hand corner to start a new chat with a single friend, or you can tap "New Group" to start a group chat with up to 100 people at once. Every group has one or more admins (if you start a group, you're the admin although you can assign others).

You might also notice a feature called Broadcast Lists under Chats. Broadcasting messaging lets you send a message to many people at once, without revealing the recipients. It's like bcc (blind carbon copy) from email, and each recipient can respond to you individually. People will need to have you in their contacts to see the message. 

The ability to create Broadcast Lists enables you to preserve a saved list of contacts to whom you send Broadcast Messages. To send a Broadcast Message to a specific contact, that person must have your phone number saved in their address book.

The fifth and final tab is Settings. Under this screen, you'll find privacy options, ways to change your notification alerts, network usage stats, a tool for archiving chats, and a place to connect your Facebook account, among many other things.

How to message in WhatsApp

While in a chat window with a friend or group, you can send anything from photos to audio files. Tap in the text field at the bottom of the chat to bring up a keyboard and enter a message, or tap the arrow symbol on the left for more options.

The arrow should bring up options to take a photo/video or send one from your library, as well as share a location or a contact. You can also send or take a photo by tapping the camera symbol found on the right side of the text field in chat.

There is also a mic symbol on the right side of the text field that you can tap in order to record and send an audio message.

You can also send GIFs or stickers

How to video or voice call in WhatsApp

To make a call, go to Calls and click the telephone+ icon in the top right. Select the contact you want and then tap the telephone or video icon. 

During any video call you always have the option to turn off your video to revert to a voice call and/or mute your microphone. Equally, you can 'upgrade' a voice call to video by enabling your camera. 

Want a group call? Select New Group Call. Check out our full guide to WhatsApp group calling.

Use WhatsApp on the web or desktop

WhatsApp isn't limited to your mobile phone. There's a web app that syncs everything from your phone. Go to the WhatsApp Web page or download the desktop app from whatsapp.com/download/

You'll need to scan a QR code using your WhatsApp app on your phone to sync it.  but after that, you'll get all your chats and conversations on your computer screen, making it nice and simple to reply. For more information on the WhatsApp desktop app, you can read our separate feature.

It'll serve up chats and alerts on your computer, allowing you to reply quickly and easily. Your phone will need to be connected for it to work though so if you lose your connection, the web app will stop syncing until you get your phone connection back.

What are the 'ticks' and last seen info?

Checkmarks appear next to each message you send. One grey checkmark indicates to you that the message was successfully sent to the recipient, while two grey checkmarks indicate when the message was successfully delivered to the recipient's phone. Two blue checkmarks alerts you when the recipient has read your message.

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When you look at a chat window or even a contact within WhatsApp, you'll often see a "Last Seen" timestamp under his or her name. It's a handy little indicator for when the contact last checked WhatsApp. If you don't want people to see when exactly you're using WhatsApp, you can hide your Last Seen timestamp. Just go to Settings, then Account, and Privacy.

Be sure to toggle Last Seen to "Nobody", but doing so will also prevent you from being able to see everybody's last seen time. Under this section, you will also see that you can hide your profile photo, status, and read receipts. You can even manage your list of blocked contacts.

Stop incoming media from automatically saving

By default, WhatsApp automatically saves images and videos from recipients to the Camera Roll on iOS devices or in Gallery or Photos app on Android.

You can stop this on iOS by going to Settings and then Chat Settings. From there, toggle off "Saving Incoming Media".

Check your WhatsApp call data usage settings

As we mentioned, WhatsApp uses your mobile data if you're not on Wi-Fi. Here's how to monitor usage. 

Mute group notifications

Group conversations can be the worst. You might not be able to leave the conversation, but you can mute notifications so you aren't awakened every time someone throws in their two cents.

If you're using an iPhone, just open the group chat, tap the subject to get the Group Info screen, and then tap Mute. In Android, open the chat, then tap the Menu button, and tap Mute.

Backup your chats

When you switch to a new phone, you can take your WhatsApp chat history with you. Just go to Settings within the app, then tap Chat Settings, and select Chat Backup.

From there, back up the chat now or turn on Auto Backup. You can restore your chats when you reinstall WhatsApp on a new phone.

This backs up to Apple iCloud or Google Drive depending on which system you're using. Be aware that you can restore chats from an iPhone to another iPhone but not between an iPhone and Android. 

Writing by Dan Grabham and Elyse Betters.