As mentioned in a previous article here (Testing For iPhone App Memory Problems), chasing down memory problems when doing iPhone app testing can be difficult. In particular, providing developers with concrete evidence that a memory issue is or is not their problem is a big challenge. Recently, while testing an iPhone app that was consistently presenting low memory alerts, we needed an independent memory assessment and discovered Memory Sweep, written by Gary Fung. It's a free app and works great for our testing purposes. Here's the information it provides you:
The numbers you see for Memory Status will help you diagnose memory problems when testing iPhone app. We used it for memory stress testing. We needed to force a low memory condition to see how an iPhone app behaved. Memory Sweep validated this process. We have a way of setting up iPhones/iPod touches so that memory is forced to be about 3-4MB. Once we do this, we launch Memory Sweep to make sure free memory is as low as we expected (you can see that free memory in the image above is 4.21MB), then quit and launch the iPhone app under test. In this way we can characterize our defects in a precise way so that the developer has confidence in the results.
When you read the reviews on Memory Sweep, you'll find that are very critical about the app. The main complaint is that the app is named Memory Sweep on the iTunes App Store and ends up being called "Scan" on your iPhone. From what I can tell, the critical reviews have been mostly about cosmetics and not functionality. There are plenty of positive reviews, particularly from those that appreciate the capability to force more memory on their iPhones. My main complaint is that this app only runs under iPhone OS 3.0. This will force us to find a similar app to run on older iPhone OS versions for our testing.