A unique film has been released in the United Kingdom, shot entirely on iPhones.

Independent filmmaker Sean Baker's small-budget film "Tangerine", on two trans sex workers in California, was shot entirely on iPhones. 

The experimental filmmaker said: "All of my films capture street life and are shot clandestinely to a certain degree, but using iPhones on this one helped to even a greater extent."

Expounding the merits of using a phone camera for a feature-length film, he said: "It led to a lot of freedom and experimentation. If you had seen us shooting across Santa Monica Boulevard, you would not know we were a professional shoot, except for perhaps our sound gear."

The film was shot using three iPhone 5s fitted with special lenses. The vivid, cinematic sheen of the footage was added during post-production by the director. Instead of using dolly shots, which require tracks to be layed for the movement of the camera, the director rode a bicycle following the actor in movement while shooting with an iPhone.

The small-budget film, produced by Magnolia Pictures, was selected for the Sundance Film Festival 2015. The film was a breakout hit at the festival, reports BBC. The filmmaker expressed surprise over the "universal love" he received for the film.

"It's the wonderful personas of the two lead characters that are really pulling audiences in," he said. "Mya introduced me to Kiki. When I saw the two of them together, I immediately thought 'dynamic duo' — we have to figure out how to get these two on the big screen."

The story revolves around the lives of trans sex workers Alexandra and Sin-Dee in California. The multi-layered narrative, which represents different subcultures in the city, is a retelling of a real-life incident narrated to the director by the two actresses.

"Tangerine" is the first film for both actresses – Mya Taylor and Kitana Kiki Rodriguez — who play Alexandra and Sin-Dee.

The actresses and the director have high expectations from the film for spreading awareness about the issues and lives of trans individuals.

Baker said: "I hope that films like this, which appeal to a greater audience, will raise awareness — and then awareness will lead to acceptance."

Mya Taylor told the BBC: "I wanted this story to be brutally real and honest, and I wanted it to be funny — and he (Sean Baker) nailed it."