Spark Inspector (US$39.99 single-license) offers an exciting new development tool. Targeting devs looking to refine their user interfaces, it enables you to interactively tweak view properties like frames and layers.
The app centers around an Interface Builder-like experience, with familiar-looking attribute and size inspectors. If you're comfortable in Xcode 4, you'll easily find your way around this tool.
In addition, it provides a custom layer inspector -- one that could (and, honestly should) inspire Apple. It enables you to update layer attributes like shadows and transforms, while viewing the results in real time.
Perfect for devs who otherwise write their interfaces in code (I am guilty as charged), it b
