So I sent an email off to one developer of my favorite automotive tracking app for my iPad, thinking if he was developing for it, he probably wouldn't have an issue supporting WP. His response was the typical "If you get more users, I'll develop" bs that you hear. My response to him was:
"At present, there is a small (in comparison to iOS and Android), yet untapped market for your application. I do like the application, as it is what I am familiar with. I do not want to invest my time and money into relearning an application.
However, if you wait until WP has X number of users before you start to develop, that will mean that X number of users will have searched for your application and then, when not finding it available, will have invested their time and money into a competing app that does the exact same thing. We will then be familiar with that app, and be used to the gestures required to make it do what we want. YOUR product will then be the unfamiliar one.
We will not then reinvest our time and money into relearning your application. Instead, the developer who offered us the product we wanted, when we wanted it, will have gotten and continue to get our money.
Your choice."