GapDebug - GapDebug is a comprehensive mobile debugging tool that bridges the gap left by other debugging options.
Chrome Mobile DevTools - Mobile Debugging Tools
Bugfender - Cloud logging for your apps, not only crashes matter
Xcode - Xcode is Apple’s powerful integrated development environment for creating great apps for Mac, iPhone, and iPad. Xcode 4 includes the Xcode IDE, instruments, iOS Simulator, and the latest Mac OS X and iOS SDKs.
Flipboard FLEX - At Flipboard, we place a high value on tools that speed up and improve the development process.
FLEX - An in-app debugging and exploration tool for iOS.