The Google/Microsoft war grows uglier.  This time, Google is refusing to allow Microsoft to have access to the YouTube API key for an app on Windows phones.

Microsoft Corporate Vice President David Howard writes a fuming open letter about the interactions between the two companies that led to Google’s decision to block the app.

If Howard’s assertions are true, it appears that Google is once again engaging in anti-competitive and monopolistic business practices.

Although there were 5 reasons given by Google for blocking the app, the main point of contention appears to be Google’s insistence that Microsoft rewrite the application to use HTML5.

In a statement to The Verge, Google says:

Microsoft has not made the browser upgrades necessary to enable a fully-featured YouTube experience, and has instead re-released a YouTube app that violates our Terms of Service….It has been disabled. We value our broad developer community and therefore ask everyone to adhere to the same guidelines.

Microsoft counters by saying that Google’s own apps on Android and iOS do not use HTML5, and they are hardly applying the “same guidelines” to everyone.

Peter Bright at ArsTechnica label Google’s demands “arbitrary,” saying “Google’s own engineers have implicitly deemed HTML5 to not be good enough by not using it themselves.”

“Google’s behavior appears to be more than a little capricious” he notes.  “Other unofficial YouTube clients exist, and thus far Google appears not to have killed them off with the same vigor it has demonstrated while going after Microsoft’s client.”

Howard’s letter concludes by once again asking that Google stop blocking the YouTube app:

We think it’s clear that Google just doesn’t want Windows Phone users to have the same experience as Android and Apple users, and that their objections are nothing other than excuses.

Google should explain why they are suddenly insisting that its competitors produce inferior apps.  And if there isn’t a good excuse, the Justice Department and the FTC should get on the stick and take action to stop Google from engaging in its continual pattern of monopolistic practices.