Question [Q] Any tutorials where professional complex apps are created from scratch?

Hey Guys.Do you know of any sites where a full blown complex app is developed from scratch ?I'm not talking about stuff that only teach you the concepts of android programming,but something where a very complex idea is the final target and you learn things along the way (while creating each part of the app).Somewhere along the lines of the book "Sams teach yourself android development in 24 hours",but with professional , well designed and complex apps.