Apple's maps have turned out to be a hit with iPhone and iPad users in the US - despite the roasting that they were given when they first appeared in September 2012.
But Google - which was kicked off the iPhone after it refused to give Apple access to its voice-driven turn-by-turn map navigation - has lost nearly 23m mobile users in the US as a result.
That is a huge fall against the 81m Google Maps mobile users it had there at its peak in September last year, according to ComScore, a market research company, which produced the figures from regular polls of thousand of users.
The introduction of Apple's own maps with its iOS 6 software in September 2012 caused a furore after it emerged that they were littered with errors. A location in Ireland named "Airfield" was marked as an airport, Paddington station had vanished, and Helsinki railway station was - it seemed - a park. The company was panned, and chief executive Tim Cook made a public apology.
But a year on, a total of 35m iPhone owners in the US used Apple's maps during September 2013, according to ComScore, compared to a total of 58.7m Google Maps across the iPhone and Android.
Of those, about 6m used Google Maps on the iPhone, according to calculations by the Guardian based on figures from ComScore. That includes 2m iPhone users who have not or cannot upgrade to iOS 6, according to data from MixPanel.
That suggests Google's efforts to offer a stand-alone app since December have gained little traction with iPhone users.
"Google has lost access to a very, very important data channel in the North American market," commented Ben Wood, mobile analyst for CCS Insight, a research company based in London. "But Apple was adamant that it wasn't going to give up on doing its own maps, even when it had problems. This is a war of attrition."