Question

I could not find an answer on this so I hope the answer is a sample yes.

Can I make the simple assumption that if I test my app on an iPhone 5 with iOS 6.0, all users using an iPhone5 with iOS 6.0 will have the same performance –Given that all apps work in silos and are allocated a specific memory space and CPU utilization when in the foreground.

Fair assumption?

Thanks

Answer 1

Whilst they are allocated their own memory space, it doesn’t mean they have access to all the memory available. Apple’s documentation describes the problem well:

There is a direct correlation between the amount of free memory available and the relative performance of your app. Less free memory means that the system is more likely to have trouble fulfilling future memory requests. If that happens, the system can always remove suspended apps, code pages, or other nonvolatile resources from memory. However, removing those apps and resources from memory may be only a temporary fix, especially if they are needed again a short time later. Instead, minimize your memory use in the first place, and clean up the memory you do use in a timely manner.

Also stuff like Disk access and CPU access depends on what is going around in the background. A user could have multiple mail accounts syncing and notifications firing and network signal searching and a whole heap of other stuff all of which may impact performance. If you are running into the case where you are running to the limits of performance it would be good to see where you can tune your application.