i want to design apps for multiple platforms. can some one help me

Question

how do i start

Answer 1

when u write a program and compile it. java program will be converted into .class file.. u can run this .class file in any platform because java is platform independent but make sure u have installed JVM in ur system( this JVM is platform dependent)

Answer 2

Just have a huge bite at these java tutorials and you're good to go

Answer 3

I uses eclipse