The United Airlines mobile application represents a comprehensive digital travel companion that handles the entire journey lifecycle from initial planning through post-flight baggage retrieval. Positioned as a market leader among airline apps, it maintains a 4.78/5 App Store rating, indicating strong user satisfaction relative to competing airline applications. The app's core functionality encompasses flight search and booking, mobile check-in with digital boarding passes, seat selection and changes, baggage management including tracking and payment, and the Travel-Ready Center for documentation verification. Particularly noteworthy is the specialized service animal registration system, which allows travelers to pre-register assistance animals and maintain their documentation within the app—a feature that received specific praise in user reviews for reducing travel stress for passengers with service animals. User experience demonstrates thoughtful design with clear information architecture and logical workflow progression. The interface provides transparent flight information, standby status updates, and real-time notifications. The bag drop shortcut feature streamlines airport procedures by allowing passengers to complete baggage tagging before arrival. Real-world usage patterns show particularly strong adoption among business travelers, families with children, and passengers requiring special assistance, with the app serving as a digital concierge throughout the travel journey. User feedback trends consistently highlight the app's reliability and comprehensive feature set. Reviewers specifically praise the intuitive interface design (Jury's out, September 4, 2025), service animal accommodation features (Jordoleib, September 3, 2025), and family travel support (pau 4 u, September 1, 2025). The September 2025 reviews indicate particular appreciation for ground staff coordination with app functionality, as mentioned by tfrgcuvtcrhcgfgg regarding baggage assistance. The application demonstrates notable strengths in its complete travel ecosystem integration and accessibility features, though some users report occasional glitches during high-traffic periods. The app excels most for United's frequent flyers, passengers with special needs, and those valuing integrated travel management. While the baggage tracking functionality proves reliable, some users note room for improvement in international flight update comprehensiveness. The app represents one of the most fully-featured airline applications available, particularly valuable for travelers seeking to minimize airport processing time.