Yep, there's no catch. The free textPlus app, by GOGII, not only brings real SMS to your iPhone or iPod Touch, but also supports group chat and landscape mode for writing (US numbers only). Which means that unlike most apps, textPlus isn't just glorified instant messaging.
textPlus is super simple to use too. Once you've installed the ad-supported application, you can open it up and click the familiar compose option to select a contact (or enter any 10 digit phone number), or two or three, and start typing and texting away.
When you're ready, hit send. Your message is conveyed over WiFi and appears as an SMS message from GOGII (60611). You can then wait for a response, or return to the conversations page to start new chats and view updates - as they happen - to existing threads.
textPlus doesn't require that you enter your own phone number to use the application, but if you do, you can opt to receive standard SMS notifications (though this kind of defeats the purpose), or participate in conversations started by others.
If there were to be a downside to textPlus, it would be that your friends who aren't using the app see an incoming message from a foreign number with your name and GOGII included, instead of a standard SMS message from you. App users might also miss the fact that their textPlus chats stay inside of the app, and don't get included with your other SMS communications to contacts.
Realistically, however, those all might seem like small sacrifices when given the opportunity to text to any contact or number free of charge. Try it out and tell us what you think of textPlus in the comments.
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