Viber (iOS|Android|Windows Phone) is excellent for messaging and calling your friends for free around the globe and you can even make video calls. You can also use your and your friends' actual phone numbers provided they have the app too.
There are a number of third party messaging apps in the App Store such asand , which let you message your friends in a similar way. But with free audio and video calls, Viber is the app to choose when you want to avoid long-distance charges, and it has plenty of extras that make it better than most popular third party messaging apps.
The only problem? Not everyone uses it. So that means you're going to have to convince your friends and family to download it too. But if you do, I think you'll be happy with everything it has to offer.
When you launch the app, you'll need to enter your phone number and give access to your contacts list. For verification, you'll also get a text message with a code you'll need to enter before your account is completely synced to your device.
Once you're set up, you can peruse the contact list to see which of your contacts also use Viber and you can invite contacts who don't.
Once you have some people to chat with, you can use Viber like most other messaging apps. You can send text messages, short audio clips, photos and videos from your library, your location, and emoticons.
Sending a message is just like other apps, with balloons for each of the people chatting, and you can set up group texts for up to 100 participants. You can create an audio clip by touching the microphone, then touching and holding a big button in the bottom center to record. It's not quite as elegant as the touch and swipe up method you get with iOS Messages, but it works just fine.
There is a doodle feature, which lets you pick a brush size and color, then draw on the screen to send little doodles to your friends. It's obviously not a crucial feature, but it's a fun addition that lets you add something more to the conversation.
The app also has stickers, which are larger, more detailed graphics than emoticons. You get a pretty large selection, but you can also buy themed sticker packs for $1.99 each through in-app purchase.