You can invite friends on WhatsApp using Tell a Friend /Invite feature. This option allows you to send an email or SMS with an official download link. In order to invite a friend to join WhatsApp, you need to follow the steps below:
- iPhone: Favorites > Scroll to the bottom > Tap Invite Friends to WhatsApp
- Android: Select contact > Scroll to the bottom > Tap Tell friends about WhatsApp
- BlackBerry: Favorites > Scroll to the bottom > Tap Invite more friends
- Nokia S60: Contacts > Select a contact > Options > Invite
- Nokia S40: All > Select a contact > Select the contact's phone number > Invite
- Windows Phone: All > Select a contact > Tap Invite (contact) to WhatsApp
- BlackBerry 10: Swipe down from the top of the screen > Tap Tell A Friend
You can check the official User Guide for further information.