WhatsApp is a hugely popular instant messaging (IM) app that lets you send text image, video, or audio to your friends, colleagues, and family over Wi-Fi and cellular data networks. That means you don't need a — potentially pricy — SMS/MMS plan from your local carrier, and that you can contact pretty much anyone, anywhere, all around the world.

WhatsApp, now owned by Facebook, supports both direct and group messaging and read state. Accounts are setup using your phone number as the only identifier, and there are no ads, in-app purchases, or other charges.

WhatsApp is free to download and use.

See at App Store

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