Question

I’m going back through one of my old apps (my first, actually), and am trying to reduce memory usage in order to stop it from crashing on older devices (I’ve run it on an old device and profiled with instruments, and it is definitely memory issues that cause it to crash). Unfortunately, when I made the app, I was not very familiar with the common practices of iOS development and structured it very poorly: with one view controller, and one xib file, hiding and showing interface elements as necessary.

Now I am wondering whether it would be worth doing a complete overhaul and starting over, with multiple classes and view controllers, and whether that will reduce the insanely high amount of memory (70+MB) needed to load the app.

Also, would it work if I just emptied out the .xib file and loaded all the interface elements programmatically (and continued using one .xib file)?

Answer 1

It’s hard to know how much it will help without knowing what’s really going on in your app. Here’s some general tips to help you out though:

• Split out your view controllers so you have one view controller per view. There are cases where a view controller should actually control multiple views (either for memory efficiency, performance, etc), but use this as a starting point.
• Don’t put all of your objects in a single XIB. Split it out so you have one XIB per view controller and let iOS load your XIB elements when needed.
• Creating interface elements programmatically isn’t going to help with memory usage.
• Watch what you cache and only keep things in memory if there’s a clear performance advantage.

If you decide to rewrite your app, be sure to profile it often using Instruments to measure your progress.