The aim of the thesis was to create a working smartphone application. Application collects wildlife data and sends it to the Finnish Wildlife Agency's server. The thesis examined PhoneGap's usage for smartphone cross-platform application development. The work was done for Oravannahka Oy, and the main goal was to make a working demo for the company. The aim was to make the application work for all the major smartphone operating system. Specifically the three most prelevant, which are Windows Phone, Android and iOS. Application was built around PhoneGap's framework. The functionality for the application was built with Javascript and the user interface was built with HTML and CSS. The main idea for the application is to report wildlife occurrences to the Finnish Wildlife Agency. User inputs data for the type occurrence that is happening and the animal that it concerns. Application uses GPS-tracking system. Tracking information and the inputted data are sent to a server, which saves them. The interface was made to be intuitive and easy to understand. The application was tested for all of the three main operating systems. The end result fulfilled expectations and a working application was delivered to the client.