Accurately predicting fire spread and behaviour on the fireline, in the field, is highly important in order to prevent the loss of human life, improve the success of initial attack and better understand the potential fire behaviour, minimizing many risks for firefighters. We present the Wildfire Analyst™ Pocket Edition application (WFA Pocket), a mobile tool aimed to be used by the fire fighter community. It shows punctual fire characteristics and estimated progression based on user introduced input data in an intuitive 3D map interface in real-time, allowing the user to interactively change parameters and analyze how the fire behaviour changes in relation to the inputs. The mathematical models implemented are all well-known by the scientific community and reported in this article. The application has integrated GIS capabilities, can work online and offline, and can retrieve fuel, weather and canopy data from online servers for the georeferenced ignition point. We describe the background and model foundation of WFA Pocket as well as its system design and main features. We also evaluate its robustness of results and present a case study to show the potential use of this tool in the field. Limitations and assumptions in the use of the application as well as potential improvements for the future are discussed.