title: Why would an iOS app act differently on two different devices?
body: <p>If you were developing an iOS app using Xcode and were testing it on different devices, is there any reason as to why it would act differently given that the devices are the same model and have the same software version?</p>
  
  <p>For example, I'd recently been working on an app. A clean build of that app were put on two different iPhone5s. (Same software version)</p>
  
  <p>However while running on one of the phones I'd get a memory deallocation error similar to the following:</p>
  
  <p><code>*** -[CFString release]: message sent to deallocated instance</code></p>
  
  <p>Where as on the other device, no such error would appear.</p>
  
  <p>Are there any obvious reasons as to why this might be the case for any app?</p>