All you budding Perez Hiltons need wait no longer. Hellotxt's app for the iPhone has been approved. Its latest iteration, Hellotxt 2.0, allows you to doodle on a photo or other graphic, prior to posting it to your social network of choice.

In addition to fun and games, this function allows social networks and their users the capacity for a bit of extra meaning. The history of annotation is a long one, stretching from classical times through the latest dial-twirling on microblogs. With a drawing function, partners in a network can save space by not having to quote the piece of information they're commenting on.

The three-year-old, Italy-based company, whom we wrote about a year ago, have distinguished itself in a crowded market that includes Hootsuite and Seesmic, with this interesting innovation. It will be interesting to see if any of its competitors pick up on it.