The whole process took about a month. I recieved a mail two days after I applied and in two weeks I had a phone interview. The interview took around 15 minutes and I was asked weather I would like to have a skype interview or a face-to-face one. I accepted a face-to-face interview since I am living in Düsseldorf. The next day, they gave me a date for my interview which was in two weeks.
The interview at Trivago office in Düsseldorf was so much fun. I was in the room with the HR representative and the team leader, they both made me feel so comfortable and I could be completely myself. It took about an hour and I was out. The next day I was offered the position.