Changing WP7 app from free to paid
windows-phone-7
Solution
Anyone who installs your app while it is free has basically purchased your app for free. So if you update the price, it won't affect those users because they've already "purchased" the app. They'll receive any further updates to the full version of your app.
Problem
I am thinking of chaqnging one my app from free to paid to further support the development. If do this change and enabled a trial, what wil hapen with existing users after they update the app from marketplace? Will they have the full paid version or will they be in trial? It does not seem fair if they wil get stuck in trial.