Edit: Though it looks like you're asking permission to update Twitter, and that's making me hesitant.
That is in the autoshare section of Settings. You remain in control at all times about posts. You can turn sharing to social networks on/off but everything defaults to off.
Also the real-time feed shows you the apps your friends are downloading now, reviews, likes etc.
We want to strengthen our Android team so if you know any good Android devs they can contact us for a job!
The site is still very clean, almost Instagr.am -ish, but we are also working on a web view where you can see and share each others app profiles (see http://www.zwapp.com/users/237 for a work in progress example).