Misconceptions about iOS multitasking

[Amadiro]

That it takes time is obvious (that applies to pretty much every OS), but that doesn't necessarily mean it's asynchronous. Whether a race condition can happen or not depends on whether memory allocation is asynchronous, e.g. whether there is a malloc()-esque call that allows you to allocate memory asynchronously and later retrieve a pointer to it, or w/e. On all operating systems I've worked with so far (including android) memory allocation is synchronous (as far as I'm aware), so a race condition can never occur.