While most of us use our smartphones to check the news or keep up with friends during MTR rides, one photographer is turning train carriages into his photography studio - and you could find yourself an unwitting model. In a city where more people have mobile phones than just about anywhere else, the top-quality lenses on the latest smartphones have made everyone a photographer, as well as a photographer's subject. For the past year, cinematographer and amateur photographer Lai Yat-nam, 33, has been taking candid images of train commuters with his iPhone on his daily trip from Sheung Wan to Kowloon Tong. He takes the photos stealthily to ensure his subjects do not shift their stances because they know someone is watching - in defiance of MTR rules that ban photography without the subject's prior permission. The results show a spectrum of unguarded moments of city life; from a young woman applying lipstick to a couple stealing a kiss while they wait for their train. There are moments of repose with heads resting on hands and eyes closed or office workers staring into the distance, deep in thought. For Lai, the train carriage is his photo studio and with the use of a smartphone application, or app, called Hipstamatic, his urban travel diary is now on show at a new exhibition called 'The Underground Scene'. It runs until March 25. A spokesman for the MTR Corporation said photography was banned on platforms and trains without prior approval. He noted that closed-circuit cameras installed on platforms and some trains could catch offenders. The spokesman did not respond to questions about Lai's show. Lai said he had never been stopped from taking pictures by security or asked to stop by commuters. 'No one's told me to stop; they just walk away if they don't want you to take a photo,' he said. It was a different story when he tried to take photos on the subway in Paris, where some passengers shouted at him to stop. While some of the Lai's images, like the black and white picture of a couple kissing on a platform in Kwun Tong, appear posed, he said they are often just the result of patience. 'I was going home and walking around the platform and I saw them kissing. I pretended to walk around before I took two photos,' he said. 'People don't notice and the images tell so many stories. You don't have to buy a Leica [camera]. The main thing is what you see and how you think.' Not all photo-taking on the MTR has such an innocent purpose. Reports of smartphones and hidden cameras being used to take pictures up the skirts of women passengers have risen in recent years and several men including a former corrections officer and an immigration official have been fined or sentenced to community service for the offence in recent years. Lai's show is the opening exhibition at a new photography studio in Jordan set up by the founders of an online photography site called Photoblog. Earlier this month, a panel of smartphone photographers gathered for a talk as part of Social Media Week, an annual event run by US-based Crowdcentric and its local partner, Cohn & Wolfe ImpactAsia. The speakers discussed ways to use the camera without someone noticing and also of the many apps that give smartphone photos an extra kick, which speaker Tyson Wheatley described as being like having 'a darkroom in your pocket'.