We've gotten a lot of feedback that the install and privacy limitations on apps in the "sandbox" make it difficult to fully test, circulate, and vet your applications.
To address those difficulties, as of today apps can be installed on up to 20 user profiles. We hope this makes it easier to test your apps with realistic user interactions, while still maintaining the security of our sandbox limitations.
Additionally, I want to clarify how you can actually facilitate other users installing your apps. Apps in "Development" (formerly "Test") mode can only be installed by users who are friends with that application's profile. However, app profiles do not have an "add to friends" button. Catch 22? Not quite, because app profiles can still send friend requests themselves. So, the workaround is to login to your app profile account and then friend the user accounts that want to install your app. Those accounts will then be able to view your app profile and install the application.
We know these aren't the easiest set of limitations to work with, but they're some of the important ways we maintain security for both end-users and developers whose apps are still under development.
As always, let us know if you have ideas for improvements.