App Store App Update Sizes

shawn744 · Apr 21, 2014

Hey guys, I've been using iPhone since it came out and I can't believe I don't know the answer to this but...I'm finding that my 16GB 5S is running low on storage very quickly...both on iCloud and the phone storage...when you have an app update that shows 40MB...that doesn't get added on to the size of the app already installed on the phone does it ? Because one of the apps, when I compare the current size to the update size, it would be 8mb smaller in size after the update..any thoughts?

Much appreciated,

-Shawn

willerz2 · Apr 22, 2014

shawn744 said:
Hey guys, I've been using iPhone since it came out and I can't believe I don't know the answer to this but...I'm finding that my 16GB 5S is running low on storage very quickly...both on iCloud and the phone storage...when you have an app update that shows 40MB...that doesn't get added on to the size of the app already installed on the phone does it ? Because one of the apps, when I compare the current size to the update size, it would be 8mb smaller in size after the update..any thoughts?

Much appreciated,

-Shawn

App updates are (usually) complete overwrites of the existing app on your device but preserves your user data, which deleting and reinstalling afresh does not do. The size of the application in the AppStore is misleading when compared to Settings.app > General > Usage, as the size that's in the AppStore refers to the IPA's size (basically Apple's version of an APK [Android's app extension] or like an .exe or .deb file if that makes any sense) and not the actual size of the app. Once you unpack the installation file, usually they are decompressed to their full size like a .zip, .rar or .deb, so you'll see a discrepancy between the AppStore size and the actual Usage size. Not sure if that makes any sense in terms of wording in explaining the size difference nominally.

For the second part of your question, if you're referring to the actual size of the app in Settings > General > Usage, it's possible that the developers cleaned up their XCode to decrease the size of the application in Usage. If you're referring to the size in the AppStore, it may be the compression factor being changed, or, like the Usage size, the developers may have cleaned up the code, which results in a smaller compressed file, which can also translate to a decrease in actual Usage size since there's less junk code laying around (i.e. Zynga Poker a couple of months back, which docked about 11MB from the Usage size and about 6MB from the AppStore size)

You can usually see the decrease in the size of both Usage and the AppStore size when an app transitions from something like iOS 4.3+ minimal support to something like iOS 7+ only support, meaning you're removing a bunch of code that's relevant in keeping support for older iOS versions. Removing support for older iOS versions will tend to drop the size of the app a bit as you may have to hard code some aspects that are not present in older iOS versions that are present in newer iOS versions (i.e. Mailbox.app when they transitioned from iOS 6+ to iOS 7+, dropping both the AppStore and Usage size by about 4MB)