The Guardian wrote:
Sources at Google familiar with its mapping plans say they are "not optimistic" that Apple will ever approve a dedicated Google Maps iOS app. Though the app is reportedly in development and should be ready to ship by the end of the year, the sources say their plans are only proceeding in "the unlikely event" that Apple will choose to approve the app.It's true that Apple not only has the ability to block any app it chooses from the App Store, it can also choose to boot an app out from the Store even if it had been in the Store for a long period.
In particular, Apple will often ban an app if it duplicates already existing content in iOS. As such, a Google Maps app would duplicate the functionality of Apple's own Maps app, which replaced Google Maps as part of iOS beginning with iOS 6.
However, Apple's Maps app was met with derision when iOS 6 was released. The Irish Minister for Justice went so far as to call it "dangerous" when it was discovered that the app labeled Airfield Garden, a working farm in a residential area, as an airport.
Things became so bad that Apple not only apologized for the SNAFU, it began recommending alternatives. Included among those were the web app version of Google Maps, Waze, Bing, and MapQuest.
Therein lies an assurance that Apple will most likely approve the Google Maps app. It's already recommending the web version of it, and the native versions of many other apps.
An earlier example is available, too: Apple removed YouTube as a default app in iOS, as its license had expired and the company no longer wanted to pay for it. In addition, Apple had to know that Google would quickly add a standalone YouTube app to the App Store.
Things were different with Google Maps, though. Apple reportedly had a year left on its deal with Google. However, the companies clashed over features available in the iOS version, and thus Apple opted to go its own way.
It's still recovering from what is one of its more recent failures.