Xcode API build really small in size.

Hello, everyone. I recently built a project on Android and the file size was 67 mb. However, recently I've built it on Xcode and the project file was 1gb - yet the actual API is only 1mb. When i uploaded it to iTunes connect it said that the store size would be also about 1mb. I find this odd, and haven't bothered testing it because it does seem extremely small. Is there something I might be doing wrong when building. Thank you all.