Best alternative texting app for iphone?

What is the best replacement app: "Messages" for the iphone? I want something that is free and good for just texting.

I'm also looking for something that will show date and time after each text.

I like Viber, it will do that and it let's you can text for free around the world. You can also make calls on Viber too. It will sync your contact list and tell you who already has Viber. The downside is that the other person has to get it too, but it is free.

Text free. No hassle. Just easy