I want to add a custom URL to my iPhone app so other apps will be able to open it, However I want the URL to begin with \"http\", in more details, I want to open the app form a
This does not work for third-party apps. Only Apple's own apps can react to certain http:// links.
You have to run the link through your site first.
For example, the link in the email could be http://<YOUR_SITE>/Q9xDH364
And this link could take them to a special page on your site. On your site, if you detect the user agent from an iPad/iPhone/iPod, you can display an alert that says something like:
If you have "MY APP" installed on your device, you can view this link in your app
Then, if the user presses ok, translate the http://<YOUR_SITE>/Q9xDH364
link into a link your app can get, such as my_app://<YOUR_SITE>/Q9xDH364
This works well for my app, Ambiance. For an example, go to http://snd.am/35 from your iPhone and your browser and see the differences.