

Ask HN: Good iOS Interview Questions - mitchf

I need some help crafting some better iOS interview questions.<p>These are the questions I've been asking, but I feel they are too
beginner/intermediate. Need some more advanced questions to find the
top talent.<p>* Explain what ARC is and how it works?
* Why does your app crash when the device is low on memory?
* What is a retain-cycle and how do you find and fix them?
* What is fast enumeration?
* How many bytes can we send to apple push notification server?
* Describe the flow of push notifications?
* What is the difference between retain &#38; assign?
* Explain the difference between a category and a protocol?
* What is Delegation in iOS?
* Assume that your app is running in the foreground but is currently not
receiving events. In which state it would be in?
* What are some distribution options for iOS apps?
* What's the process for publishing to the App Store?
* What does it mean to call objective-c a messaging language?<p>I appreciate your feedback!
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icodestuff
What are four uses of categories and what other construct can you replace each
of them with (bonus: when should you replace them with those constructs)?

Explain the interior pointer problem, when it applies, and what you can do
about it.

Describe what happens in objc_msgSend, and give two reasons why it's
implemented in assembly rather than C.

How would you implement NSMutableSet?

Explain the proper uses of (__bridge), (__bridge_retained) and
(__bridge_transfer) casts.

Explain all the important differences between direct ivar access and access
through a property, under MRC and under ARC.

When should you use +/-conformsToProtocol: instead of +/-respondsToSelector:?

How would you implement toll-free bridging?

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bstahlhood
Just a few off the top of my head, hope this helps:

\- Explain the relationship between a UIView and a CALayer

\- When it comes to animation, what are the differences between animatable
properties on a UIView and a CALayer.

\- How would you go about creating an UIImage and using Core Graphics
primitives outside of a drawRect method.

\- When initializing ivars in a UIViewController being used in a XIB or
Storyboard, which method would you want to override?

\- Walk through the flow of a UIVIewController. What methods get called and in
which order?

\- How would you check to see if an object implements a protocol?

\- What is KVO? Give an example of how to use it.

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roberte3
Write a doubly linked list in C#. (I shit you not, I had a large consultancy
interview me for an IOS position and this was the one interview question that
they asked).

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michaelkscott
Maybe they had Xamarin in mind when they asked you that:
<http://xamarin.com/monotouch>

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tagabek
If the interviewee has an app in the App Store, a good option might be to let
them tell you about the technical details. Go over their code and ask them to
explain everything. In the right situation, this may be a good section to add
on to the questions you already have.

