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 users across the iPhone and Android base.

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."

European and other regional data for maps use is not available, but is expected to mirror that found in the US.

Huge value

Map data is hugely valuable both for Apple and Google in monitoring traffic flows to offer information on traffic jams, and determining user location, which is generally fed back anonymously to the relevant companies. Google also uses it to provide location-related advertising on its search and maps - an increasingly important source of income as search revenue from desktop sites flattens. Google has been aggressively pushing adverts into its maps app on all platforms since August.

For Apple, the growth in maps users is important so that it can improve its own traffic and other data relating to phone signal strength. Apple, however, is a relative minnow in location-based advertising, and has principally focussed on using the data for traffic forecasts for drivers.

The break with the iPhone came when Apple became frustrated in late 2009 by Google's refusal to provide turn-by-turn navigation for maps on the iPhone - a feature which was available on Google's own Android, and which is hugely useful for car drivers. "They broke their promise," one Apple executive told the Guardian. Google also wanted to collect more data from Apple users via maps, such as through its Latitude product, and held off offering vector graphics (which store data more efficiently, and can work offline). That sparked Apple's decision to develop its own maps offering, licensing data from TomTom and other providers.

But the introduction was a public relations fiasco, and after the initial criticism, Cook fired Scott Forstall, the head of the iPhone software team, and maps chief Richard Williamson soon afterwards.

In his apology, Cook urged people to download alternative maps apps - though Google did not then have one available for the iPhone. When it came out in December, it shot to the top of the download charts, with 10m downloads within 48 hours.

Default behaviour

ComScore's data suggests though that comparatively few iPhone owners actually take the trouble to use Google's maps rather than Apple's - in part because Apple's maps are the default for any driving directions or map-related search on iOS 6 and above.

According to ComScore, in September 2012 - just ahead of the introduction of Apple Maps - there were a total of 81.1m users of Google Maps, out of a total of 103.6m iPhones and Android phones users.

But a year later, its smartphone data says that the total number of Google Maps users is much lower, at 43% of iPhone and Android users - or 58.7m, despite the user base growing to 136.7m.

"For the average user, even if they have the Google Maps app, they don't use it a lot," said Andrew Lipsman, an analyst at ComScore. "In a narrow window [after the iOS app download became available] I'm sure there was a ton of activity, but only for a short period."

ComScore's data shows that in September 2013, 35m used Apple's maps at least once during the month, out of a total iPhone population of 60.1m. The 58% usage on the iPhone is reckoned to reflect the growing number of younger users who do not use mapping services; the proportion of iPhone users who use any mapping service, including Google's, has been dropping since April 2012, according to ComScore's data.

Wood said: "The thing is, on an iPhone all roads lead to Apple's maps. They're putting this front and centre for users, and getting more confident." For Google, he said, "They're very fortunate that Android is a big source of data - they will be very relieved at that." He cautioned that US iPhone users might be more eager to use Apple's maps because there seem to be fewer errors there compared to other regions, including Europe.

Google told the Guardian: "We’re not currently sharing details on the number of downloads. While we can’t disclose specific performance metrics, we’re pleased with the product and user feedback has been positive."

Calculating the data

According to ComScore, which collects data from tens of thousands of US smartphone users every month, in September 2012 there were 81.1m users of Google Maps in total across the 103.6m users of iPhones and Android smartphones.

Facebook v Google Maps use in the US in 2012, millions of users. The number of Google Maps users dips in September as iOS 6 is rolled out. Photograph: /PR/ComScore

But as iOS 6 began to roll out, and introduced Apple's maps as the default, the number using Google Maps dropped precipitously, even as the number of iPhones and Android phones began rising. (ComScore does not measure usage on Windows Phone or BlackBerry, which comprise only about 10% of smartphones in use in the US.) By December 2012, even though the base of iPhones and Android phones had grown to 112.9m - up 9.3m - the total number across both platforms using Google Maps on mobile at least once a month had dropped, to 74.4m.

Latest figures from ComScore, published for September 2013, say that the total number of iPhones and Android phones in the US has grown to 136.7m, the number who used the Google Maps app has kept dropping - down to 58.8m - while the number of Apple Maps users stands at 35m out of a total iPhone population of 60.1m.

The picture is made more complicated because there are differing rates of usage of maps between the two platforms - and it has changed over the measurement period. In April 2012, ComScore was quoted saying that in the US there were 31.3m iPhone users of Google Maps, and 38.2m users on Android (from a collective base of 88.4m devices, implying a 78% usage rate).

It also noted that iOS users tended to use maps more often - 9.7m used it once a day, against 7.2m for Android. In addition, iPhone users spent longer on maps than Android users - 75.5 minutes per month, against 56.2 minutes for Android.

But since then, according to ComScore, the usage rates for maps has altered, particularly as the iPhone has gained a younger base. According to Lipsman, by September 2013 "overall map usage is [now] a bit higher on Android (79% of users) than on iPhone (72% of users)."

Modelling that change in users suggests that on the iPhone, there are about 43.2m maps users in all - which would break down to 35m using Apple's maps, and another 8.3m who use Google's maps at least once a month.

Separate data from Mixpanel for the US supplied to the Guardian suggests though that there are about 2m iPhone owners in the US who have not upgraded their phones to iOS 6, and so cannot use Apple's maps.

That means that Google has gone from having at least 31m users on the iPhone in April 2012 - and perhaps as many as 35m in September 2012, based on a model using a sliding scale of maps ownership - to around 6.3m who are using it monthly on iOS 6 and above.

Update: one query that has been raised is about Waze, a traffic app which was bought in June 2013 by Google. Might US iPhone users be using Waze in preference to Apple Maps - but in effect benefiting Google?

ComScore's figures do not show Waze in the top 15 mobile apps in September 2013, for which the smallest share is 18.0% (for Facebook Messenger). That would suggest Waze was used by fewer than 24.6m people in the US in that month (18% of 136.7m base). Nor does Waze appear in ComScore's figures for July or August, the months in which maps use is highest because Americans travel (often by road) for holidays.

Worldwide, Waze's user base was "nearly 50m" in July 2013, according to Yahoo. That's a worldwide figure, and includes not just iPhones and Android (for which a client has been available since 2009), but also BlackBerry, Windows Mobile, Windows Phone, Symbian and Maemo. Without data from the company, it's impossible to know how many users Waze has on the iPhone in the US, since there's no indication of the platform or geographical split for this Israel-based company. But it seems unlikely that the loss of iPhone users of Google Maps has been made up by users of Waze.