Question

I’m facing the iOS app size issue that the app size over 50 MB cannot be downloaded over 3G/4G connection. My iOS app is heavy because of large amount of images (.png). I have already tried some solutions but it’s not enough.

1. Separate between iPhone and iPad.
2. Use Compressing PNGs Technique but this just reduce my app size little.
3. Use zip archiving like SSZipArchive.

I saw an app with download size less than 50 MB but after downloading and installing the usage size is more than 100 MB. How this can be done?

I think they may download some resources later in some way but I do not know how. Any one please give me some suggestions. Thank you.

EDIT:
The texture package sprite-sheet of format such .pvr.ccz also be used. This can be handle the same way as .png.

Answer 1

Yes most apps do this. Since you are talking about .png they already go through 2-stage compression. So I dont think further compressing or zip is going to help you.

Lets say you have several heavy images which bloat up your app size. So you remove those heavy images from app packaging and when the user downloads the app for the first time, at that time fetch those images as static files using usual http. You could either do this in a separate setup step (showing progress bar et al.) or you could download these images at runtime based on what the user does in your app.

Once you fetch them you can keep these images locally in your app documents folder or any other folder & serve them up locally from next time onwards (see SDWebCache). or you could keep it simple at make it pure http calls (no locally storing) but this might impact your users experience.