Android java native app

OUR BUSINESS IS DOOR STEP HOME SERVICES.

IT HAS 3 APPLICATIONS
CUSTOMER APP (https://play.google.com/store/apps/details?id=in.localhelper.android)
TECHNICIAN APP
ADMIN APP

WE HAVE DEVELOPED APPLICATION FOR CUSTOMER ALSO WE HAVE APPLICATION FOR TECHNICIAN AS WELL AS ADMIN.

CUSTOMER APPLICATION NEEDS TO BE UPDATED
WHEREAS TECHNICIAN APP & ADMIN APP SHOULD BE CREATED.

APPS SHOULD BE CREATED USING FIREBASE DATABASE.

I WILL SHARE EXISTING APP CODE.