You Can able to download the source code of the created application in OREOPS. Both direct from browser or send the source code to email as specified. Source contains both Android and IOS files. You can execute and preview the app by using the downloaded source in both Android Studio and Xcode.
The below attached files will gives the steps and prerequisites on how to preview the source code in Android studio and Xcode.
OREOPS | Source Code Preview in Android Studio
OREOPS | Source Code Preview in Xcode IOS Emulator