After my post on Tuesday about Apple’s support for Transit maps in iOS 6, a few things have come to light that are worth noting. Andy Baio provides an excellent overview of the relevant issues involved, and Philip Bump at Grist has some screenshots (hat tip to Shawn Medero in the comments).
For the non-techie, the gist is this: when a developer submits a “routing” iPhone app to Apple, they include instructions about what parts of the world their routing app provides routing for. So, for example, Metro might submit an app that covers the entirety of King County. If you’re looking for directions within those coordinates, then Apple will show you a link to the Metro app which you can download and get directions.
Presumably there will be routing apps for most cities by the time iOS is released. Heck, it’s possible Google will submit an app and list “the whole planet” as coordinates, which would make it effectively the same as the current setup. Apple seems to be indicating that they wouldn’t reject such an app, but we’ll see.
One more point worth bringing up in this discussion: it’s worth taking a minute to be clear about what we mean by a “routing app.” There are (at least) three tasks one might want a transit app to provide:
- Bus & train routes and stops (where does the bus go?)
- Real-time arrival information (is the bus on time?)
- Routing (get me from Point A to Point B at Time C)
1 & 2 are relatively straightforward* assuming the transit agency provides the appropriate data feeds. This is what OneBusAway provides, for example. Routing is much trickier, because it involves making complicated decisions about when to take which mode and when to transfer, walk, etc. Google does this reasonably well (though far from perfect) on a global scale. Specific agencies typically do this quite well within their specific domains, but can choke when trying to hand old between agencies. Initiatives like Open Trip Planner exist in part to solve this problem.
Sound Transit’s online trip planner is actually reasonably good at routing across agencies and offers a nice mobile-optimized web interface (though not an app yet). Nevertheless, it’s quite likely that by the time iOS 6 ships in the fall, iPhone users in Puget Sound will have a pretty decent solution.
* “straightforward” does not imply “easy.” The OBA folks put a lot of work into their app, but it’s a different problem than point-to-point routing.