You'll need atleast a Master in Computer Science and somewhat know every major programming language (C, C#, C++, Java, HTML, etc.) But the most important Languages will be: C and HTML.
Start with C then C++... You can begin by buying and reading this book: http://amzn.com/0131103628
it's a cheap book and it's really short. Don't move past any programming example until you fully understand what it's doing and WHY.
S4Lt0S is correct
asking what languages you need to know is like asking "what dishes do I need to know how to cook to get a job at a 5 star restaurant ?"
the answer is -- if you graduated from a decent cooking school and have a few years experience then it doesn't mater what you know how to cook because if I give you a new dish you've never done before your experience and knowledge should enable you to prepare the dish well
and it's the exact same thing with programming
Apple doesn't care what languages you know
they assume that because you graduated from a decent university and because you have a few years of experience that you will be able to teach yourself any language you need to know
and if technology progresses so that existing languages don't fit your needs then YOU will be able to write your own language (Java or Swift for example)
if you want a job at Apple then you need a BS in computer science, and preferably an MS
you'll need a few years of advanced math (calculus and discrete math)
you'll learn a few languages in school, but what's important is that you'll learn how languages work
you'll learn how to write your own language, how to write compilers, how to write operating systems (and it will not matter what the language is)
Q:) what kinds of things do I need to know how to build before I can get a job as a master carpenter ?
A:) if you're a master carpenter then you'll be able to build anything I ask you to build
For this you have to learn C C++ Java
C & HTML for sure.
.NET
http://mstechnologies.org/
