Voting is now open for the winner of Six Degrees of Summer, a new project from O2 Guru TV in which award-winning British directors have made a short film shot entirely on smartphones.

The directors were asked to shoot a 3-minute segment expressing their vision of British summertime celebration. But there's a twist! Each director was only allowed to see the closing moments of the preceding film and had to begin their narrative at that point.

Watch the project's curator, BAFTA-winner Tom Shankland, explain more...

> Watch the finalists' videos and vote here.

Take a look behind the scenes at School's Out, the project's first shoot, as director Tom Shankland reveals some of the unusual challenges of filming on a smartphone...

> Subscribe to O2GuruTV's YouTube channel.

The completed film will be premiered on O2 Guru TV next month.