Tumblr is a mini-blogging service that allows easy sharing of media. Its main competitors include classical blogging platforms like Wordpress and Blogger, microblogging sites like Twitter, and other "tumblelogging" sites like Soap.io and Publr.com that have similar features to Tumblr. Tumblr has competitive advantages over these alternatives through its simplicity, customizability, active community, and support for collaborative posting and embedded media. The document proposes several business development ideas for Tumblr to generate revenues, such as advertising, third-party applications, premium services, and mobile or ecommerce offerings.