Android Ringtone App

I'm looking to create an Android ringtone app with following features:

Primary Functionality:
- Users can set ringtones as:
- Call ringtone
- Notification sound
- Share ringtones with friends

Customization:
- Fade in/out effects
- Volume control
- Online database
Ideal Skills and Experience:
- Android app development
- Experience with audio manipulation
- UI/UX design for mobile applications
- Familiarity with sharing functionalities in apps

Please provide portfolios showcasing similar work.