Melissa Rodrigues, a children's author, initially disbelieved her son's midnight report of an intruder outside their house in Waikanae, north of Wellington.
However, after discovering footprints in the frost in their backyard and their gate wide open one night Rodrigues and her husband started exploring security options.
The couple downloaded a smartphone app called Salient Eye, which overrides the phone's camera to capture images whenever it senses motion. It then emails the images to the owner.
The family left the porch light on so the smartphone could capture images, 'stuff.Co.Nz' reported.
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At about 4.40am local time stop-motion photos from the app began flooding into Rodrigues' email, showing the family someone was outside at that moment, reaching over their porch.
"It gave me the shock of a lifetime because, even though I was waiting for it, I wasn't expecting to see him," said Rodrigues, who immediately called the police.
Senior Sergeant Anita Dixon of Kapiti Police said the makeshift surveillance system helped police to catch the intruder and arrest him.
The offender who was a teenager and has been referred to Youth Aid.