WhatsApp is a cross-platform smartphone app that lets you send text and picture messages for free, using your data allowance.

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For example, with messages, why click off to Google Talk or Google Voice when you can send Facebook messages (or text messages) direct through Facebook?

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These are the profile pictures of people who send you Facebook messages or text messages via Messenger.

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In addition to any Facebook messages or calls you already send or make, Facebook Home pulls SMS text messages into the mix.

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As long as your friends can receive pictures and text messages, you can send content to their phone.

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Although most airlines limit this to send and receive text messages, you still have a full GSM connection with your phone, tablet, or laptop.

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Sites like mint.com can be set up to send text messages to your phone if you start spending more than your target in a particular area.

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Even though the Galaxy Player isn't a cellphone, it can make voice and video calls, and send text messages over the Internet when you're in Wi-Fi range.

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They can send premium SMS text messages that actually cost you money and put money in the hands of the person who is writing the premium SMS service.

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Then there is digital technology: instead of arriving on the dot, you can send a text message apologising for being late (with nearly 25 billion messages sent in 2005, Germany is one of Europe's text-messaging champions).

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