Don't need image 开发者_如何学编程background, just good-looking color is enough.
Jeff LaMarche has some very iOS-looking and simple-to-use programmatic gradient buttons here.
You just need to add a .h and .m file to your project and you are good to go.
http://www.youthedesigner.com/2010/03/10/29-sexy-iphone-app-designs/
http://www.smashingmagazine.com/2009/10/09/iphone-app-design-trends/
These may not be of any use but check them out. There are some really well designed apps and u'll get a good idea of what colours work. Your question is slightly vague to provide an exact answer IMO.
You can get the RBB values of the colours using a number of tools.
Check this
Fun With UIButtons and Core Animation Layers
精彩评论