Very easy, they explain the way they work and salary model, then you ask questions related to your interest. No case or anything like that. Seems they pick you on a CV base and references.
Preguntas de entrevista [1]
Pregunta 1
They ask to tell about your experience, which stack and models you worked with and what you did.
Me postulé en línea. El proceso tomó 3 días. Acudí a una entrevista en Webstep (Oslo) en feb 2015
Entrevista
First you have a chat with one of the managers, Webstep is a pretty lean company. They show you how Webstep works, their salary structure, clients and such.
You then get a change to introduce yourself, talk about what you do, what you want etc.
Webstep only hires senior consultants, i.e. 5 years of experience or more , during the meeting your CV is gone through, talk about particular clients but nothing special.
After that, you get a call if they feel you are a good fit or not.