I'm not sure exactly what your looking for or coming from, beginner or seasoned pro. There are a bunch IDE's and languages that support Mobile Development. Here are a few:
Visual Studio
-- C++
-- .NET
ArianeSoft PPL
-- Cish /
VB hybrid language
J2ME
-- Java
Silverlight
-- XAML
Flash CS
-- Actionscript
Edit: Mortscript - Forgot about that. Thanks 6700Yuma