I applied online. The process took 3 weeks. I interviewed at Growth Intelligence (London, England) in May 2017
Interview
In order,
1) Applied online
2) Phone screen (asked about the company, and software engineering projects)
3) Online test (fairly easy, converting a descriptive algorithm into a working solution)
4) On-site interview (I had to prepare a presentation ahead of the interview, and basic object-oriented questions)
5) Day-In-Office programming task (an opportunity to get a feel of the team, office culture and to showcase your programming skills)