I applied online. The process took 4 weeks. I interviewed at Citi (London, England) in Nov 2015
Interview
Submit application online, normal form logistical stuff plus a cover letter and CV - online test (shorter test but tougher than other banks!) - AC which is a case study, three competency interviews with people from the business, and a group project.
Generally a pretty good experience and a bunch of really nice intelligent people.
I had a behavioral with a current analyst, then a Superday with 3 members of the division. During the Superday, I was also assigned a case study to be conducted and presented live to the Superday interviewers.
Interview with HR and a current analyst (behavioral + CV). Another round where there was 2 interviews from people from the department and then a prresentation based on a document they present
I had 2 interviews. First one was general interview with 2 company employees, they asked about my experiences. Second one was interview with case study. with more specific technical questions.