As an Android user, I am sick of developers picking iOS over Android as their initial mobile launch. It may be that I don't understand the difficulty of porting between OS'es, or that about half of Android users are running a nearly 3-year-old version of it. But when something like Vine, which has the engineering power of Twitter behind it, forgoes the majority of the smartphone market by making an iOS-only application, it irks me. Remember, it was only after Instagram released on Android that it sold for $1 billion.
That is why I am starting this list. It is all the applications that I have seen or tried that don't bother to cater to my sector of the market. I will try to update it frequently, as I find out about new ones (and there are always new ones).