1- No, it will not.
2-, which depend on the OS version on mobile devices
3- you need to create a mobile application from the very beginning, using mobile controls and Mobile web form (form for mobile web applications) instead of a web form.
all of these controls are under this namespace:
using System.Web.UI.MobileControls;
This will allow your application to run on more than 200 types of mobile devices.
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