If you have already an app with other developer/agency and you want to move to us.
- For iOS
No problem here, we can update your app
- For Android.
We will need the keystore certificate that the android app was signed with.
Without that key , alias and password there is no way to update any existing app in Google Play store.
So the only way is to ask your developer - agency to give you the keystore for your android app.
If you plan to leave us and go to another company to make your app, we will give you the keystore for you Android app. We make new keystore for each new app.