1st Round: It was very interactive and Interview were not bound to one approach. 2nd Round: Taken by someone from android team. a) He asked about a secure approach by which only a legitimate user from mobile phone can start bounce bike. I gave him an approach in which a hashing certificate will be generated to server side when ever user will be signed up and sync that certificate to Bounce Bike, when ever it will come online. Now, Use a authenticator mechanism(same as Google Authenticator) to authenticate the ride based on hash key matching of certificate. It seems to be Interviewer was not happy with my approach inspite of It passed all of his pre-assumed use-cases. b) He want to discuss my Architecture approach for Application development. I explained him How MVP work with clean architecture, But It seems to be he was either only interested in MVVM or He might have designed his MVP architecture using some approach and looking for the same from my side. But, As I know Architecture design of any system vary from developer to developer. c) 2 DS algo questions * There are three unsorted(confirmed twice from him) array of size x, y, z. I had to form a third array whose size will be (n + m + l) and put all the elements in sorted order. I solved this question in O(N log N) Time complexity, where N = (x + y + z). But he told me provide a logic with less than this time complexity, which is not possible as I know(Please correct me If I am wrong). * Parenthesis balance question. I solved this in O(n) time complexity and and O(n) space complexity, which is clean solution as per Leet-code also. But, He was expecting a solution with O(1) space complexity. I failed to provide this solution, Because I don't want to play with the Time complexity. As per GeeksForGeeks (that he might have seen partially), You can achieve O(1) space complexity with a Time complexity of O(n^2) and O(n^3), which is not recommendable.