If you are in a supermarket facing shelf after shelf of cooking oil, how do you pick the healthiest one?

You could soon learn how to choose between canola, coconut, palm and sunflower oil by playing Buy Which? on your smartphone.

This is a prototype "serious game" created by the National Healthcare Group's (NHG) health promotion department and local game developer Mojocat. Serious games are simulations of real-world events that combine entertainment with education.

More such games are in the pipeline with yesterday's launch of the inaugural Health Innovation Technology Challenge, a contest to develop such games in the area of healthcare. The contest is organised by the NHG, Serious Games Association (SGA) and Infocomm Development Authority.

Professor Philip Choo, group chief executive officer of the NHG, said serious games can motivate patients by introducing tangible short-term and long-term challenges, as well as a reward structure.

The contest is open to all healthcare organisations. Submissions have to be made online at www.hit2016.seriousgamesconference.org by April 18.

Shortlisted entries will be given three months and technical support to develop a prototype, before two rounds of presentations in August and September. The top three teams will receive prize money of between $1,000 and $3,000.

The contest builds on last year's NHG-SGA Game Jam, which explored how serious games with interactive technology can improve patient care.

Four teams have had their ideas developed into prototypes and Buy Which? is one of them. It puts players in a virtual supermarket, and teaches them nutritional principles and how to read food labels to make healthier food choices.

Players can play against their friends and rack up scores for selecting the right answer. The game is still being tested and does not have a launch date yet.

Dr Audrey Tan, senior consultant at NHG, said: "The supermarket setting simulates real life, and our aim to influence their behaviour in this decision-making process."