Ionic cordova build command

I am using Ionic 3 for one of my app.
To generate ios build I used ionic cordova build ios --prod command & generated ipa from xcode.

How above command is different from ionic cordova build ios --prod --device? Can it be used to generate app store build?

Edit1:
Reason why I asked this question:
I have integrated an SDK which only support real devices not simulators. So when I build using command ionic cordova build ios --prod it fails giving missing architecture errors.
When I run ionic cordova build ios --prod --device, it succeeded. But that SDK is not included in ios project now.