After signing in, you can view your prototypes under the Prototypes tab.

Tap each prototype to load it onto your phone. Once this is complete, you’ll be able to view them offline in addition to any prototype share links which you have downloaded.
By default, prototypes will be sorted alphanumerically, but once you start using the app, the prototypes will reorder according to what’s been opened most recently.
You can search for prototypes by type or name by tapping the spotlight icon at the top right of your screen and entering a name or type, such as iPad, iPhone, Android, and so on.
Sample prototypes will not appear in the list of prototypes.
If you tap a screen in an area without a hotspot, you’ll be able to view hotspot areas. You'll also be able tap and hold on any screen to open a menu that allows you to refresh all screens, enter comment mode, view all screens, or exit the prototype.