It's easy to use, simple yet very powerful tool that helps me debug my apps with ease. I can see any thread related issues in real time while using it. The app itself looks too complicated at first but after some initial training you will be able to navigate through your code easily. There are few bugs which i have reported already. So far they seem really serious problems so hopefully this gets fixed soon! We were having lots of crashing issue when our users used their iPhones during long meetings or presentations etc. This has been solved now by spark inspector as we don't need to wait till crash happens before finding out what causes it.