It follows the acquisition of Misfit by fashion retailer and watchmaker Fossil Group in November last year for $260m (£198.4m), which signalled a move to expand the brand globally.
Ranieri’s brief includes PR, events and influencer campaigns targeting the lifestyle, health and fitness and tech sectors. Ranieri will work with Pride PR in the Netherlands, which is heading up a network of PR agencies across Europe.
Buckinghamshire-based Ranieri, which was appointed following a competitive pitch, previously worked with Misfit to launch its Shine activity tracker in the UK in 2014. The UK PR work was later taken in-house prior to the Fossil Group acquisition.
Misfit’s other wearable fitness tracker products include Ray and Speedo Shine 2, a collaboration with the swimwear brand.
Niels Van der Valk of Misfit said: "Ranieri has extensive experience in our target markets and can develop insightful ideas that will work in this space."
Sculley was among the original investors in Misfit when it launched in San Francisco in 2011. He was Apple CEO for 10 years from 1983, and before that was president of Pepsi.
With wearable tech and personal health tech tipped as areas for growth in the business world, and consequently the PR market, Hotwire launched a new global health tech practice last month.