Me neither, I was referring to the publishing process: He wanted to make sure, that the app runs well on WP7, before porting the app to WP8 for the new features and resolutions, what took months. Now he has to develop the two apps in parallel. (At least that's how I understood it.)
If that is really how Jay does it, I'm sure he has his reasons. The people I know don't do it that way. Microsoft has a
platform compatibility page devoted specifically to this issue, on which is stated:
"In general, the Windows Phone app platform enables apps that target Windows Phone OS 7.1 to run without modification or recompilation on Windows Phone 8."
That means one app. No parallel development.
Also, if apps support the new resolutions, aren't they automatically not compatible to WP7 anymore? I'm not sure, but if this is true, every app that can really support my device, won't work for WP7 anymore, or there have again to be two apps developed in parallel.
No. WP8 is smarter than that. :wink: It has to be, because many WP8 devices still use 800x480 resolutions, remember? Microsoft describes how this works
here. It basically comes down to WP UI rendering being pixel agnostic. Actually, every single WP7 app should already have been capable of taking full advantage of your 8x's resolution without any black bars. Many app developers just didn't get it right the first time. Some still don't get it.
For everything else, yes, you're right. But for how long will this last? The Lumia 900 was still really new when WP8 hit. So people who have bought a high end device at the end of the year have now maybe passed three months of their 2 year update cycle. Do you think the support will still be the same in a year when they are left with 9 months?
Anyone who bought a Lumia 900 three months ago, when the 920 was already available, probably doesn't care that much about updates. However, anyone that cares about their phones as much as we do, would have known to wait a week and then get a newer WP8 device instead. Beyond that though, you are right of course. Support for older devices will slowly dwindle over time. Over what time period is hard to say. Consider however, that brand new WP7 devices are still being sold today. The newest model, the 510, was released just last December. WP7 isn't going away for quite some time. When WP9 is released, WP8 will stick around in exactly the same way... to service the low end...