GroupMe is a mobile group messaging app owned by Microsoft. It was launched in May 2010 by the private company GroupMe. In August 2011, GroupMe delivered over 100 million messages each month and by June 2012, that number jumped to 550 million. In 2013, GroupMe had over 12 million registered users.
GroupMe is like a private chat room for your small group. Have as many as you want, and it's always free. Now, you can coordinate with coworkers, organize a game night, and keep in touch with family all in the same place.