Phone companies make lots of money charging for each SMS aka Text message. When sending texts to other iOS users, your iPhone’s built-in Messages app can route text messages over your dataplan, avoiding any SMS charges by your phone company and saving you money.
MacLife has a detailed post on this topic:
- How to Make Sure your iPhone Sends iMessages instead of Text, Cory Bohon, Maclife.com, Feb 25 2013
iMessage background information:
- Messages Unlimited texting. Unlimited fun., apple.com/ios/messages
More tips: carleton.ca/iteam/tips