Why are smartphones not approved for use as GPS devices in aviation?

Smartphones are not approved for use as GPS devices in aviation primarily because they do not meet the certification standards set for aviation use. More specifically, they are not certified GPS units such as those that comply with Technical Standard Orders (TSO) like TSO-129 and TSO-145. These standards ensure that aviation equipment meets rigorous performance, reliability, and safety requirements essential for navigating aircraft.

In aviation, the integrity and reliability of navigation data are critical for safe operations, especially under instrument flight rules (IFR). Certified GPS units undergo extensive testing and validation to ensure they provide accurate and dependable information, which is crucial during all phases of flight, particularly in challenging conditions or emergencies.

While other options mention various concerns related to smartphones, they do not encapsulate the fundamental issue of certification, which is the core reason why smartphones are not recognized as acceptable GPS devices for aviation. The lack of certification implies that using smartphones can pose a risk due to potential inaccuracies and unproven reliability during flight operations.