TechCrunch reports this morning that Facebook is changing the rules (again) for third party developers. They’ve done this a few times. So has Apple, on the iPhone platform – when they can be bothered to fully explain the rules in the first place.  Meanwhile, Motorola introduced Droid today – the new flagship Android 2.0 sliding keyboard phone.  Unlike Facebook and Apple, Android is an open platform, without Google guarding the gates for developers. And developers are already complaining that the in-market mix of Android 1.5, 1.6 and 2.0 is driving development costs towards an unsustainable endpoint.

All of this has got me thinking about the challenges of building applications on other people’s platforms.  Whatever users may say about Windows, Microsoft has always treated its ISV partners pretty well.  Lots of notice, and no arbitrary barriers to deployment (Apple) or random, substantive policy and feature swings (Facebook).

I have no deep insight here, but I’m curious – particularly in our area of healthcare informatics and public health, how much is platform instability (and profusion!) limiting the development of next-generation applications?  What’s required to justify an investment in these platforms?

As for Android – depending on what the reviews look like, I’ll probably get a Droid next week or the week after, despite my Sprint contract.  I’ve been fully fed up with Windows Mobile for a while, don’t like Blackberrys, and need a sliding keyboard. Hope the application developers keep up…