Sharing and testing apps in progress has historically been limited to just fellow app developers. This has made testing apps on any large scale prior to release difficult. We’re happy to announce that we’ve updated the developer site to easily let you manage and add who has development and testing access to your apps.
From the My Apps section of the developer site you can now click the “Developers & Testers” link to view a paged list of your friends along with a “Developers” and “Test Users” column.

Simply drag and drop any of your friends into the “Test Users” column and they’ll have immediate access to view and use your app in progress.
Any of your friends that are registered developers (indicated by an asterisks [“*”] next to their display name) can be dragged into the Developers column where they will have full rights to your app source code.