I am looking forward to create an app for Android, and I am confused with the platform to choose. I am a web developer with basic knowledge in JAVA and OOPS. The app is pretty simple that will play with the adress book contacts and then sync them online and vice versa.
Which platform should I choose, Appcelerator, Phonegap or should I learn JAVA ?
For an app with less animation and CPU intensive tasks, like the one you described, I would recommend Phonegap. If you need to in the future, you can port your app over to iOS with Phonegap. Basic knowledge in Java should suffice as Phonegap is built with HTML and JavaScript.