Cross-Platform Management App Development

I need a comprehensive management app for my small business with the following essential functions: - Employee Management - Inventory Tracking - Customer Relationship Management The app should support iOS, Android, and Web platforms, ensuring a seamless experience across all devices... (Budget: $1500 - $3000 AUD, Jobs: Android, Android App Development, iOS Development, iPhone, Mobile App Development, UI / User Interface, Web Development, Website Design)