For more detailed information, visit Corona's building tutorials:
Android – http://docs.coronalabs.com/guide/distribution/androidBuild
iOS – http://docs.coronalabs.com/guide/distribution/iOSBuild
The last step once you have prepared you App for submision is to Publish it to the Stores.
Don’t forget that you need an iOS Developer Account ($99/year) and a Google Developer Account ($35) to be able to publish your apps to the stores.
But wait... isn’t Worona free?
Yes it is! But each company or person who wants to publish an app in the App Store or Google Play must have an iOS Developer Account ($99/year) and a Google Developer Account ($35).
That money is not for us, but for Apple and Google. Right now, there is no other way to publish an app to those stores.
Alternatively, we offer a Publish to the Stores Service, where you don’t have to deal with the complex registration and submission process. You can either choose to publish it under our own Apple and Google accounts (which is cheaper) or we can create new accounts only for you.