One of my friends appeared for the integrated Ph.D. Math at IISc Bangalore and shared her experience of the same. A total of 72 students had been shortlisted for the interview and her interview took place on the last day. As she entered the room, they asked for her introduction and her interest to which she told them it was analysis. She was asked the following questions
The entire interview was based on the above questions which my friend was not able to answer most of the time and thus did not get selected. However, she learned a lot from that interview and summed the entire experience in these points
So, overall the experience was very knowledgeable and I hope it's so for you too.