If you are interested in getting started with mobile development and if you like to start with iOS, I bumped into a great resource to learn Swift. There are tons of sample projects and great video walkthroughs as well as source codes of the projects you can download from GitHub.
Lessons Page:
https://swifteducation.github.io/teaching_app_development_with_swift/
Available on iTunesU to follow lessons on mobile devices:
https://itunes.apple.com/us/course/app-development-teaching-swift/id1003406963
Sample projects’ source codes:
https://github.com/swifteducation