Apple Maps quickly became the butt of jokes when it debuted in 2012. It overlooked many towns and businesses and misplaced famous landmarks. It marked New York's Madison Square Garden arena as park space because of the word "Garden." The service was a rare blunder for a company known for simple, easy-to-use products.

It's a different story three years later.

Apple fixed errors as users submitted them. It quietly bought several mapping companies, mostly for their engineers and other talent. This fall, it added transit directions for several major cities, narrowing a major gap with Google. Apple Maps is now used more widely than Google Maps on iPhones.

"They really did a great job in a short amount of time," said Alex Mackenzie-Torres, a former Google Maps manager who's now with competing transit app Moovit. "Apple has something that few companies have — simplicity in design mixed with high doses of pragmatism and practicality."

Apple's significant investment in fixing Maps underscores how important maps and related services are to tech companies. Location is key to helping phone users find restaurants and shops, discover things to do and just get around. It's also big business, as app makers tap into the core mapping functions of phones to direct people in helpful ways and sometimes offer them bargains based on where they're standing.

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The quick turnaround also demonstrates how easily companies like Apple can steer people to their own services. Google Maps and various third-party apps offer many features that Apple Maps lacks, yet Apple cleverly turned user inertia to its advantage. Many people use Apple Maps just because it comes with the phone. Even if you've taken the trouble to download a competing app, other iPhone services such as Siri and Mail will invariably take you to Apple Maps.

Without the ability to steer users this way, Apple "would not be in the position they are in," IDC analyst John Jackson said. "Not that they aren't improving the experience, but this helps the cause."

Apple says its mapping service is now used more than three times as often as its next leading competitor on iPhones and iPads, with more than 5 billion map-related requests each week. Research firm comScore says Apple has a modest lead over Google on iPhones in the U.S., though comScore measures how many people use a service in a given month rather than how often.