Modify iOS and Android App v2

Modify iOS and Android app and put in App store and Google Play. I am budgetting roughly $450 for this project as I think it is small and most of the components are already in place for iOS I have an existing iOS and Android app. The iOS app is for iPhone and iPad (not wearable); while the Android app is for all Android devices (not wearable) - the Android app may have to be created. I AM LOOKING FOR A DEVELOPER WHO CAN PROGRAM FOR BOTH IOS AND ANDROID. I AM "NOT" LOOKING FOR A TEAM AND SOMEONE WHO WILL FIND A DEVELOPER! Currently, both software use a webview to display content from a remote site; if a certain token is not seen in the url, then a native form is shown where the user has to enter a 16 digit registration key -- once the key is entered, then it will display the designated web content. THIS NEEDS TO CHANGE. What I want to change ------------------------------------ 1. Change the background image of the app (currently water droplets) 2. A native device icon appears above the top right section of the webview. Update that icon to receive JSON. If no JSON is received, or if it is empty, hide the icon. If it receives objects, they will determine what links will appear and the left slide bar when the icon is clicked. The links should be native to the device and allow user to set new URL for the webview. 3. Put a loading icon, which I will provide in the center-middle of the webview. When the app is started, and the webview is still loading its content, this icon should remain visible. 4. Remove the old app registration page where the user enters hexadecimal characters inside fields. 6. The JSON that is returned will have information such as the icon, app name, url, etc. 7. If the user is not authenticated, and they first open the app, they will be redirected to a login screen. After login, the webview should then disappear and the background image of the app should appear (image for your reference provided).