Links to books and video tutorials for learning more about Android (and iOS) development.
When searching the web for information it is easy to forget the primary source of information: the Android SDK site from Google. It has some decent text tutorials that everyone should read.
Videos from Marakana, one of the top educators in Android development. Very well structured for beginners. Many hours of video.
A video course on Youtube from PHPAcademy that teaches the basics of the Java language. Not in the context of Android, but still a good foundation for learning the Java language.
Google I/O is the main conference for developers using Google technologies. Not just for Android development, but this link is a list of the Android-related sessions that were given in 2012. Older years are also available and may still contain good and relevant knowledge. Not for beginners since they do assume some previous experience in Android development.
A beginner and an advanced e-book in the form of a subscription from Mark Murphy, the top author on Android development outside of Google. Also available in print although a bit old now. Older pdfs are also freely availble on the site (look for "Four-to-Free").
When you feel a little bit more comfortable with building Android applications, this is the book that will help you dig deeper into different parts of the platform. The link goes to Safari Books Online.
Recordings from Stanford University course CS193P is legendary for learning iOS development. They are published as part of Apple's iTunes U and you will need to view/download them from within the iTunes application.
This is the main developer conference that Apple organizes usually every year in the spring. All sessions are recorded and published in iTunes to members of the iOS Developer Program. The sessions are quite advanced since the conference is targeted at experienced iOS developers.