How can you trust some of the Android applications?

I downloaded and installed NewsRob to use as my RSS reader.

As I started it up and went to configure it, I stopped cold at the username / password screen. The app is asking for my Gmail username / password screen.

How can I trust that applications like this which are not from Google itself, won't store my gmail username / password for malicious purposes? Even if they don't intentionally do so, how can I be sure my username / password may not be inadvertently hacked by some 3rd party for malicious purposes?

Does anyone here have any insight on how we can trust 3rd party apps with our private information data? Do these apps not store usernames / passwords? How can this be verified?

Here's an article that articulates this better than me: http://www.androidguys.com/2009/10/04/5-nice-apps-i-refuse-to-use/

I'd love to hear how we can get over our fear of giving our private info out to 3rd party apps.