Apple released an update to its iPhone and iPad operating system on Wednesday that replaces Google Maps with Apple's own application. Early upgraders are reporting that the new maps are less detailed, look weird and misplace landmarks. It's shaping up to be a rare setback for Apple.

"It's a complete failure," said Jeffrey Jorgensen. "It's slower, its directions are poorer and its location data doesn't seem to be accurate. All around, it's not quite there yet."

Jorgensen, a user interface designer for a San Francisco-based startup, began using Apple Maps months ago, because Apple made it available early to people in its software development program. He said he finds himself relying on Google Maps running on his wife's Android phone instead.

The most-hyped feature of the new app is a "Flyby" mode that shows three-dimensional renderings of buildings and other features. It presents a convincing depiction of the canyons of Manhattan, but has a hard time rendering bridges and highway overpasses, which tend to look wobbly or partly collapsed.

The Apple app also has a tendency to judge landscape features by their names. For instance, it marks the hulking Madison Square Garden arena in New York as green park space because of the word "Garden" in its name. The TD Garden football stadium in Boston gets the same treatment.

Conversely, Apple Maps marks "Airfield Gardens," a farm and plant nursery in Dublin, Ireland, as an airfield. This prompted the country's Justice Minister, Alan Shatter, to warn pilots on Thursday not to land there.

"Clearly the designation is not only wrong but is dangerously misleading in that it could result in a pilot, unfamiliar with the area, in an emergency situation and without other available information, attempting a landing," he said.

Marcus Thielking, the co-founder of mapping-app developer Skobbler, said the lapses of the Apple app are surprising, particularly since Apple purchases map data from an established provider, Tele Atlas.

"The combination of Apple and TomTom screwing up something like this is very odd. Apple is not the first and only company using Tele Atlas maps," Thielking said.

Tele Atlas is a subsidiary of TomTom, a Dutch maker of navigation devices.

"We launched this new map service knowing it is a major initiative and we are just getting started," said Apple spokeswoman Trudy Muller. The app will work better the more people use it, she said, alluding to fact that users can report errors and omissions from within the app.

Google has been in the mapping game for much longer, giving it the benefit of years of error reports to help shape its maps.

There's been a Google Maps app on the iPhone since it was launched in 2007, but it's always come with the operating system. Now that it's gone from the list of "core" apps, users are finding that it's not available for download either. Google says its goal is to make Maps available, but hasn't said when that will be.

In the meantime, iPhone and iPad owners can access maps.google.com through their browser, said Google spokesman Nate Tyler. The browser version has fewer features but uses a comprehensive mapping database, he said.

Last year, Apple released another software product that many regard as half-baked: the voice-controlled virtual assistant Siri. But Siri's ability to —at least sometimes— understand spoken queries was something most users hadn't met before, so they forgave its lapses. With Maps, Apple is replacing an app nearly every smartphone user is already familiar with.

User reaction on social media has been fierce. One Twitter user quipped that the lines of people queuing up to buy the iPhone 5 on Friday will be shorter, because the buyers will be misled by the new Maps.