App Size Limit and Finding the size of your app

Question

Okay, so i've read countless places saying the app size limit is either 20 mb and some say it's 50mb... which is it?

More importantly, my current app has an "estimate app store size" of 106.1mb in the Archive section of the Organizer. HOWEVER, when I distribute it to an ad-hoc file, it comes out as a .ipa which has the size of 48.3mb. Which one should I use, and I'm confused as to why they are so different.

Answer 1

The official (and reliably up to date) resource for this is the Uploading Your Binary section of the iTunes Connect Guide (expand the 'To begin the Ready to Upload Binary flow' section). At the time of this edit it states:

iOS App binary files can be as large as 2 GB, but the executable file (app_name.app/app_name) cannot exceed 60 MB. However, consider download times when determining your app’s size. Minimize the file’s size as much as possible, keeping in mind that there is a 100 MB limit for over-the-air downloads.

Over-the-air download limit means apps below this threshold can be downloaded with a mobile data connection (anything above the limit requires a WiFi connection, or to be downloaded through iTunes on the computer). This is important as many users may not have ready access to WiFi and you don't want to prevent them from being able to get your app!

Also the .ipa is a compressed, encrypted zip file, whereas the archive is just a fully inflated package of the app, which is why the file sizes are different. The .ipa file size is the one that will be used in the App Store, so use that as your reference for total size. That said, the smaller you can make your app, obviously the happier the user will be!

Answer 2

Apple recently bumped up the size from 20 to 50 shortly after WWDC '12. I am not sure if it was officially announced, but was observed in the error message of larger apps.

Use the IPA size. The files sent from the app store are compressed. Perhaps the 106.1 is the uncompressed size, or it is a bug.