Mutual Mobile Android Engineer interview questions

I had applied online. I first got a call from HR, she asked general information about me. Then she scheduled a telephonic interview with an android engineer in a week. Interview went so well I answered almost all the questions correctly, don't know the reason behind my rejection. Apparently, they got a better candidate. The HR emailed me that even though they think I have an excellent skill set, the team has decided to move forward with another candidate at this time.