This is not in the developers interests usually. I have heard release exclusives but they all almost have expiration dates.
> Their way gives the power to the user. The user copies across iOS app binary and system libraries and it's done.
While it may empower users, it's not widely practical. (IANAL) You also have a problem that it's near impossible to get the apps off the device (you can download them with iTunes on the desktop though), then you have to decrypt them of their FairPlay encryption, and then transfer them to an Android device without possibly violating several licenses, the DMCA, and few copyrights along the way.
Providing an SDK for developers to cross compile their apps means that the apps are built and optimized specifically for Android when compiled and the distribution is not an issue for the developers because it's just like any other app on Android. It also allows the developer to integrate and provide support for system features specifically on Android.
> They don't need to be commercially viable because they're a research project.
It's not that it's not commercially viable but that highly impractical. It's will be hard to distribute and make very accessible and usable for users.
As part of a thought experiment I got Mono running on top of Apportable's platform (I used to work on Mono myself ironically). We just work at a lower level at Apportable.
Xamarin has great high level tools for developing apps if you want to write in C#. We rely on the tools the developers already use and know (mainly Xcode) to develop for other platforms while also providing you a native userland that has most of the same native APIs and frameworks you find on iOS (and most Unix like environments) that you don't get on Android out of the box.
So, the user gets to violate the Apple copyrights. sigh
Additionally, copyright doesn't disallow you from copying a file from one device you own to another. Copyright is about the distribution of ideas between people, not about arrangements of bits.
People seem to have this disgust of Copyright / paying for music / paying for films / paying for software and justify it with vague arguments about "fat cats" and "sticking it to the man" but then would obviously object to people taking their own stuff....
That said, it is fun to say "fuck the man", and often doing the right thing coincides with it for a while. Rhetoric like that can be a good way to get some people out of their comfort zones on topics like copyright, and then more nuanced analysis can lead to the realization of the importance of building sustainable, respectful means of production. DRM, Copyright, etc. are net losses to society. They may be the only way 100mm-dollar-budget movies can exist, but I think it's better to have a culture where the people have democratic control over the objects of their culture instead of being at the mercy of content conglomerates, cease-and-desist letters for fan works, and geographic youtube restrictions.
You may say that copyright is a loss to society, but as an individual that is part of the society, I would be losing out from your infringement of my copyright. That would mean that my individual loss would equate to a loss within that society.
Or am I not part of society? Does my copyright mean nothing to you?
Exclusives in the mobile industry are vanishingly rare. This wasn't always the case; Nvidia had a bunch of exclusive games (or at least exclusive on Android; they were mostly iOS ports) when they brought out the Tegra 2, and Samsung and Amazon have occasionally had time-limited exclusives on high-profile properties like Angry Birds, but it doesn't really make much sense for the developer, and seems to have largely stopped.
Their way gives the power to the user. The user copies across iOS app binary and system libraries and it's done.
Basically, your way empowers the developer, their way empowers the user.
You need to be commercially viable because your investors demand it. The price you charge developers may prevent some developers from porting their app.
They don't need to be commercially viable because they're a research project. If they release their source code, the community of hackers will develop a free and easy to install system to allow users to run any iOS app on Android.