Xcode iOS framework icon meanings

Question

When using Xcode 7.3 to add an iOS Framework to an iOS project (General -> Linked Frameworks and Libraries), Xcode uses two different icons to represent iOS frameworks. One looks like a white cube and the other looks like a toolbox. What do each of these icons mean?

Answer 1

The toolbox icon represents a framework that uses Foundation. The white cube (lego piece) represents any bundle that links against the Cocoa/Cocoa Touch frameworks.