Consumers will now be able to track fat and sugar content in their food when new mobile phone application launches in Melbourne on Monday.

The new Traffic Light Food Tracker will allow shoppers to see "traffic light" ratings that show the amount of fat, sugar and salt in packaged foods. Red warnings on foods show a high fat, sugar and salt content while green labels indicate a healthier option.

The app was developed by the Obesity Policy Coalition (OPC) to promote healthier eating habits in Australians. The OPC is calling on government to have mandatory traffic light labels on all packaged foods.

A review of Australia's food labeling laws earlier this year failed to recommend a mandatory traffic light for foods. The Federal Government is due to discuss the recommendation for compulsory traffic light labeling later this year.

Obesity Policy Coalition spokeswoman Jane Martin says the system can improve people's eating habits.

"We believe if traffic lights were mandatory on all packaged foods it would guide and empower consumers to make healthier choices for themselves and their families - that's certainly what the evidence shows," she said.

"It has been used in a voluntary capacity in the UK. For a category like ready meals with the traffic lights, sales of the healthy ready meals went up and sales of the unhealthy ready meals went down."

"Our research shows consumers want to know how much salt, sugar, saturated fat and total fat, is in the products they buy.

"Traffic light labels provide this information at a glance, and help shoppers sort the fat from the fiction."

The app rates foods by their sodium, sugars, total fat and saturated fats. High amounts of these content will get a rating of red while medium will warrant an amber rating and low amounts will get a green rating. Users can save each item in their "pantry" in the phone app for future reference.