WhatsApp on Android and iPhone directly integrates with your contact book. As long as a contact is on WhatsApp, they'll show up in the app. But you can also quickly add a contact to WhatsApp directly in the app.
How to Add a Contact in WhatsApp on Android
If someone hands you a business card and you quickly want to get the conversation started in WhatsApp, add them as a contact directly in WhatsApp. When you do this, the person's information will be synced to your contact book (and to Google, depending on your settings).
To do this, open the WhatsApp app for Android, go to the "Chats" section, and tap the "New Message" button found in the bottom-right corner.
Here, choose the "New Contact" option.
You'll now see all of the usual fields. Type in their name, company details, and their phone number. From there, tap the "Save" button.
You can now search for the user and start a conversation right away.
Alternatively, you can also easily add a contact from a contact card. To do this, tap the "Add Contact" button from the contact card.
WhatsApp will ask you if you want to add it to an existing contact or if you want to create a new one. It's best to create a new contact here, so choose the "New" option.
You'll now see the default screen for adding a new contact, with all the details filled it. Just tap the "Save" button to save the contact.
How to Add a Contact in WhatsApp on iPhone
The process on the iPhone for adding a contact is slightly different. After opening the WhatsApp app for iPhone, go to the "Chats" section and tap the "New Message" icon from the top-right corner.
Here, choose the "New Contact" option.
From this screen, enter the contact details, such as the person's name, company, and the contact number (WhatsApp will also tell you if the number is on WhatsApp or not). Then tap the "Save" button.
The contact has now been added to WhatsApp and the contact book on your iPhone. You can search for them and start chatting away.
You can also add a new contact from a contact card. Here, tap the "Save Contact" button.
From the pop-up, choose the "Create New Contact" button to create a new contact entry.
You'll now see the contact details screen with all of the available information already filled in. You can add more details here if you want. Then tap the "Save" button to add the contact to both WhatsApp and your contact book.
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