GreatCall is advertising mobile phones for "Baby Boomers and their parents" with big buttons, easy-to-read displays, and simplified UI. This is ingenious, and I expect they'll be quite successful.
One of the phones features three big dial buttons. Although the middle button is configurable (along with a contact list: do-it-yourself, ask a friend or have us update your phone list and features at your personal, secure Jitterbug web page) the marketing pictures show it labeled "tow".
Because your elderly parents who can't manage a phone with actual numbers on it should be driving.