iOS 6 maps with TomTomShipments of private navigation devices are in decline as more everyone is ready to download free and paid-for mobile apps that supply turn-by-turn maps.

While shipments of PNDs declined by 5m between 2011 to 2012, from 33m to 28m, monthly users of turn-by-turn mobile apps have grown from 105m to 150m. Greater than half this usage comes from apps that pre-installed on handsets from the likes of Google, Nokia, Apple and Blackberry. Berg Insight, which created the report, predicts that PND use will fall to 17m by 2017.

Although portion of this decline is attributed to lower consumer spending after the financial crisis, there’s a saturation in lots of mature markets that isn’t being countered by shipment growth in Eastern Europe, Latin America and India. The devices are facing competition from smartphone apps, either pre-installed, free or paid-for, and could struggle more as car manufacturers offer satnav in-car as standard, the report said.

TomTom, perhaps the foremost well-known and successful sat nav system in the world, has already made efforts to diversify its proposition. Last week the company launched a GPS sports watch that runs on Nike’s ecosystem and integrates with other popular exercise platforms. Its mapping system is also being used inside the latest version of iOS.

App developers and operators don’t seem to be immune from financial pressure, the report adds, and they’re now seeking to monetise services by introducing advertising and premium features like traffic information, speed camera alerts and automobile parking space information. “Stimulating usage is vital for app developers and mobile operators that need to pursue additional revenues from advertising”, said  André Malm, senior analyst at Berg Insight.