updated 09:53 pm EDT, Tue May 7, 2013
Lets devs bypass Safari and use Chrome as default in-app browser
Shortly after updating its GMail iOS app to allow it to link directly to Chrome and other Google apps as needed, the search and ad giant is now offering Chrome for iOS integration tools to developers that allow them to specify Chrome as the browser to use for in-app web interaction, bypassing Safari unless Chrome is not already installed. The tools can give developers the option of using Chrome or asking the user if they would like to open a link in Chrome rather than Safari. It's not yet clear if the changes represent any breach of Apple's iOS guidelines.
Because it is the default browser in iOS, nearly all web calls inside apps on iOS are handled by Mobile Safari's WebKit engine. Despite the differences between Safari and Chrome on the desktop, Chrome for iOS uses the same WebKit as Safari, meaning that the change is more symbolic than substantial. Developers of third-party iOS apps can using the new OpenInChromeController class with x-callback, that allows the app to open a web page in Chrome and return back to the app with a custom-named back button.
The app will first check to see if Chrome is installed, and if so send links to Chrome with or without the callback function. It can even be specified to open the target web page in a new tab. Google's previous update to GMail allows direct links to some of its other apps, including YouTube and Google Maps rather than Apple's Maps app. Of course, iOS has allowed direct links to other apps since the beginning -- YouTube links in apps such as Facebook have always been able to be directly routed to an installed YouTube app, for example.
The change here, however, is that now Google is attempting to bypass Apple-made apps such as Maps, Mail and now Safari. On the one hand, this offers iOS app developers and users more choice, but on the other hand it may undermine the iOS experience as envisioned by Apple and conceivably create a security risk should Chrome be found to have some exploitable flaw. It remains to be seen if Apple will let the changes by Google stand, or modify its guidelines to prevent further erosion of its strong grip on the iOS experience.