App devs listen up. If you don't have a privacy policy written for your application you need one! Take a look at this story of some developers in the State of California that defied an order to revile their privacy policies for their apps.
When the state Attorney General in California asks you for something - you better take notice. The developers were asked to post a written notice of their privacy policy and didn't.
You might be thinking, why do I need a privacy policy? The reason is mobile is big, and privacy is always a concern when you are trusting a market (iOS, Android, etc.) to deliver an app to your device safely. If there is ever a question about your apps source code, what it's accessing on the device, and how you are using the data you might be gathering you better be prepared to answer.
A privacy policy might not completely protect you as a developer, but it's a good start for you and your users.
“We assume that app developers are interested in delivering the best experience,” said Parker Higgins, an activist with the Electronic Frontier Foundation who has followed mobile app development and security closely. “But if they are malicious, it’s a little bit more difficult.”