Android

android/app/src/main/AndroidManifest.xml

<manifest
  ...
>
  <application
    ...
    android:usesCleartextTraffic="true" // 추가
  >
    ...
  </application>
</manifest>

iOS

ios/project/info.plist

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSAllowsArbitraryLoads</key> // 추가
    <true/> // 추가
    <key>NSExceptionDomains</key>
    <dict>
        <key>localhost</key>
        <dict>
            <key>NSExceptionAllowsInsecureHTTPLoads</key>
            <true/>
        </dict>
    </dict>
</dict>