The child-friendly gifts that came with McDonalds Happy Meals used to be simple toys, usually part of a promotional campaign for a family friendly movie or television show. The latest item to be included in the iconic box is considerably more high-tech however – a fitness tracker.

The fast food giant will be swapping out the traditional toy in Happy Meals for a Step-It fitness tracker for a limited time in the US and Canada, the latest step in its goal to project a healthier image for the brand.

According to USA Today, the Step-It fitness trackers will come in six colours and can track the number of steps taken by a user, blinking to represent how fast the person is moving. The devices are part of a larger campaign by McDonalds encouraging children to have an active lifestyle.

McDonalds has taken several steps over the past 15 years to address consumer concerns over the health impact of its food, placing a focus on natural ingredients and introducing menu items like salads.

In 2011, McDonalds began offering fruit or yogurt with its Happy Meals following pressure from consumer groups and healthy eating advocates, and also cut the size of french fry portions with childrens meals.

Update: McDonalds has now withdrawn the fitness trackers over concerns they might cause skin irritation. Read our full update here.

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