For those individuals without bluetooth integration in their cars, it's difficult to find an app that will read SMS messages and can be easily turned on using NFC tags (as an NFC tag can be placed on the dashboard of a car and be programmed to automatically launch Garrulo when activated - see the information about "NFC Setup", below, for more details).
Garrulo solves this problem by providing a simple interface that reads text messages as you receive them.
As time goes on, it's likely that Garrulo will provide more functionality than just SMS messages, including allowing emails, Facebook messages, Tweets, etc... to be read aloud, if desired.
For how to use Garrulo, please see https://github.com/glasstowerstudios/garrulo#garrulo
Garrulo is an open source application. You can view the source code and information about how to contribute at https://github.com/glasstowerstudios/garrulo