The robbery happened by the zebra crossing near the open-air carpark by the cinema, at about 3.30pm on Saturday June 15.
Two 15-year-old schoolboys were approached by two men who threatened them into handing over cash and an iPhone4.
The first suspect is white, aged 17 to 18, 6ft 1ins tall, and skinny. He had a big nose and a local accent.
The other suspect is white, aged 17 to 19 years, 6ft tall and slim. He had a small head and a spot on one of his cheeks. He was wearing a dark woollen hat with a bobble on.