Here's a list of keyboard shortcuts for the Mac app:
Workspace: ⌘ + Shift + A
Create Project or Styleguide: ⌘ + N
Dashboard: ⌘ + Shift + D
Styleguide: ⌘ + Shift + G
Flows: ⌘ + Shift + L
Preview screen in larger window: Screen + Space bar
Jump to Next Screen: →
Jump to Previous Screen: ←
Jump to Screen: ⌘ + J
Create a new Section from selection: ⌃ + ⌘ + N
Collapse all Sections: ⌃ + ⌘ + ↑
Expand all Sections: ⌃ + ⌘ + ↓
Edit name of Screen: ⌘ + R
Delete Screen: ⌘ + Backspace
Search screen: ⌘ + F
Manage tags: ⌘ + T
Zoom In: ⌘ + +
Zoom Out: ⌘ + -
Actual Size: ⌘ + 0
Zoom to Fit: ⌘ + 1
Zoom to Selection: ⌘ + 2
Show/hide screen grid: ⌥ + ⌘ + G
Expand sections: ⌥ + ⌘ + ↑
Collapse sections: ⌥ + ⌘ + ↓