I applied through my college job portal. After you have applied, you have to give a test on Hackerrank and also a virtual interview. My Hackerrank test had 3-4 questions, standard questions (nothing too tough), but you should be prepared well. Virtual interview asks about 4-6 behavioral questions and probably 2-3 very basic technical questions. (OOPs concepts, GET vs. POST etc) . Once you get selected through the online process, you get to go to their On-Site location ( Vegas :D ).
The On-site process is so muuuch fun! The people at Zappos, especially the recruiters, make sure you're comfortable and try to connect you with potential future team members. On-site process involves another coding round, an HR interview, and finally a whiteboard coding technical interview.
Coding interview - Techies at Zappos give you a problem and you have to code the solution.
HR interview has another set of behavioral questions lined up for you. (some are pretty tough, nevertheless, my advice to anyone is that "just be yourself", if you happen to be in that situation.)
Technical interview is easy, they ask you basic algorithmic questions ( I was asked questions from topics like string operations and hashmaps. They also asked about time complexity of the code that I had written).