No dev is going to share source on making a phone/contact app. It is up to you to read, search, experiment and try yourself. Some dev may share some knowledge (after you have made an attempt yourself), but they will not give you everything for free. You need to do some (most) of the work yourself
“When I was 5 years old, my mother always told me that happiness was the key to life. When I went to school, they asked me what I wanted to be when I grew up. I wrote down 'happy'. They told me I didn't understand the assignment, and I told them they didn't understand life.” ~ John Lennon
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?