In the root directory there is a app-release.apk file which can either be installed manually or via adb on either simulator/hardware device. quiz_app.ipa can be installed on ios devices.
In order to build or to develop the application it's required to follow getting-started guide from react-native website: https://facebook.github.io/react-native/docs/getting-started
npm install
or
yarn
Android:
react-native run-android
iOS:
react-native run-ios
if you are using xcode 12 and have problems installing third-party libraries run this:
node_modules/react-native && scripts/ios-install-third-party.sh && cd third-party && cd glog-0.3.5 && ./configure --host arm-apple-darwin && cd ../../../../
and then change xcode build system from new one to the legacy one, then try building app again. If issues with third-party libraries persist, check these issues carefully: facebook/react-native#21168 facebook/react-native#21274 facebook/react-native#19839