The Lionel LionChief App is a free lifestyle app available for Android devices. It is developed by Lionel LLC and allows users to control their Lionel LionChief, LionChief Plus, LionChief+2.0, FlyerChief, and newer Legacy BLE locomotives. The app offers a unique experience where users can select their locomotive from multiple available icons and then control it using the app.

The app provides all the features of the Lionel LionChief hardware remote control and adds additional features such as individual volume controls, pitch customization of bell and whistle, remote smoke on/off, speed limit, momentum, and more. Users can also watch a video on how to install and use the app via the link provided. Overall, the Lionel LionChief App is a great addition to any Lionel train enthusiast's collection, providing a convenient and modern way to control their train.