You simply add them by using the + button on the main view.
Absolutely. We don't send your data to our servers and all traffic between the Peopls app and the social media sites is encrypted.
We're working on that and it should be ready later in the summer 2014.
Sorry, not right now.
Your friends need to allow third party apps to view their public profiles.
Yes, there is a 1Password shortcut button in the navigation bar. You'll need the latest version of 1Password.