Ah, thanks for the correction. Been also confused as I thought this was going to be another app (like WhatsApp I currently use to txt between iOS devices), to differentiate between paid and free messages. Being integrated into Messages I guess you just have to be aware what the device on the other end is (or ignore the little, but ridiculous, cost of each). Have I mentioned how much I hate paying for text messages on smart phones with IM/email easily available?