What does "ig" mean in texting?

In texting, the abbreviation "IG" is short for Instagram. Instagram is a free photograph sharing application and social network that is often abbreviated in texting and other short-form communication applications.

Instagram is a top social media platform as of 2014. Similar applications and websites, such as Pinterest, Twitter, Foursquare, Tumblr and Flickr, have similar functions. However, Instagram has grown tremendously over the past four years. Within two months of its release, the network amassed 1 million users. In 2012, Facebook, another social network giant, purchased Instagram for $1 billion. Across the world, there are over 150 million active Instagram users as of 2014.