The presentation was given by Grzesiek Sikorski (grzegorz.sikorski@sigmapoint.co) at FreshTalk #17 - a morning tech talk organised by KoalaMetrics and Sigmapoint. We meet every two weeks in Krakow to talk about mobile technology, mobile apps, Android, iOS and data science. For more info check out our meetup website (http://www.meetup.com/FreshTalk/) or the event blog (http://koalametrics.github.io/).