I used to work there and I have interviewed few candidates.
The process starts with recruiter conversing with the candidates. After initial HR screening, the team that the candidate will be working with performs technical phone screening. It usually consists of a team leader and few developers. For Android related position, it mostly was basic android questions : fragments, activities, lifecycle, views, threading, OO related questions. There is usually no algorithm questions at this point. Usually, the software team is very nice and invite as much people as possible to on-site. They are mostly looking for people who knows the basics and are also cool/chill/fun to work with. Main point is to answer as much questions as possible and be friendly
If the candidate is good enough and knows the basics, they are invited to a on-site or remote conferencing interview. On-site interview consists of company tour, walking around with HR (I'm not sure what they exactly do but HR always just brought them to us when we were waiting for the candidate). The interview with the software team consisted of 30-45 minutes of code test where user has to create a very simple app. I would think it is an easiest app (would take a developer around 10-20 minutes to create) but I've seen a lot of candidates struggle with it since they might nervous to code it in front of people watching. If you are interviewing, just concentrate on creating something functional and shows your ability to code and your structure or create apps.
The above information for around beginning of 2014. My interview (Jan/Feb 2013) was a varied a little but overall consisted of same process.
