While Apple plans to debut its own mass transit directions service for Maps in iOS 9 as soon as June, the rollout will not be as ambitious as some users may have hoped. In its first iteration, Apple’s Transit service will only support approximately a half-dozen cities across the United States, Canada, and Europe, in addition to China, according to sources…

In the United States, the planned launch cities are San Francisco and New York, two major metropolitan areas that are known for public transportation, while Toronto will be likely Canada’s sole representative for the iOS 9 Maps Transit feature at launch. In Europe, Apple is said to be gearing up to first launch the feature in London, Paris, and Berlin.

While Apple has accumulated its own data for North America and Europe, Apple is working with longtime partner AutoNavi to source transit data for China. Pre-existing agreements currently prohibit Apple from collecting its own transit maps data in China, according to a source, and Apple already utilizes AutoNavi data for pre-existing Maps features for iPhones in China.

While these are the planned cities for this fall’s iOS 9 launch, Apple is already working on its next round of cities. Apple considers Boston, Massachusetts and Tokyo, Japan as its next two priority cities after the initial launch, but Tokyo support may be farther out due to the region’s expansive transit service offerings. Los Angeles, pictured in our mockup above from last year, is low on Apple’s transit priority list, the sources added.

As we noted in our original article on the transit feature for iOS 9 Maps, Apple has developed the ability to dynamically add more cities to the Maps app over-the-air, not requiring a full iOS software update. Apple will also be able to notify users via a push notification as support is added in their current city of residence, we noted in our previous report. Apple does not yet notify users of new geographical support for features.

Apple currently plans to unveil its Maps Transit features at its Worldwide Developers Conference keynote address on Monday, June 8th. Besides this new Maps tentpole feature, Apple plans to introduce a new systemwide typeface called San Francisco, a Home app for controlling approved HomeKit devices, several security and optimization upgrades, enhancements to the Messages and Health apps, iPad split-screen apps, and a new built-in keyboard.