I said cheap and then, of course, if it is free I do not mind. That means that I am willing to pay if it is cheaper than the normal charge. Like I said, imessage is limitted to IOS and whatsapp is limitted to users who have the app. I am not interested in this kind of apps.
I work on a secure alternative to whatsapp called
Gliph (see sig) and we're very interested in what people want out of SMS.
You mentioned low price, I wanted to share the cost of sending SMS to China Telecom, China Unicom and China Mobile, which is 6.7¢ / msg. That is pricing
directly from Twilio (scroll down and type in China to see).
Given that the cost to an app developer is 6.7 cents per message, and want to make up to 3-5 cents on their own to pay for their development costs, would you pay 10-11 cents per SMS to China? Is that cheaper than your normal charge you pay?
If it is too high of a price, is there a particular reason why it must be SMS? Are the other people you want to message with not using iPhone / smart phones?
Rob