How should I prepare for Apple onsite interview for software engineer new grad?

This should help get you started:

Overall

  • 6 hours of interviews
  • Overall 9 rounds and 1 recruiter round during the Onsite Interview and a phone screen prior to the onsite Interview

Specifics

Non Tech:

  • What Is your favourite Apple product/service
  • What is the most embarrassing song you have on your phone?
  • What is different about Apple?
  • What do you notice when you walk into an Apple Store?
  • Tell me about a time when you had to quickly adapt to something new.

Tech

  • They ask a lot of OS X and iOS memory management questions
  • Run time of a binary search tree
  • Find the most frequent element in an integer array
  • Android trivia questions - use a hashmap counter
  • Do you know what asymptotic means?
  • Why can't you use primitives in a hashmap.
  • Assorted HTML/CSS questions.
  • How would you design a data structure that is an array, but with so many elements such that the array almost fills up the entire RAM?
  • How does delegation work?
  • How does ARC work in Objective C, and how is it different from garbage collection?
  • Difference between strong and weak pointers?

Questions taken from Apple Software Engineer Interview Questions broadly.

I hope this helps!