Sherlock is a GPS tracking device connected to a mobile app, providing cyclists with a handy and reliable solution for monitoring the position of their bicycles in every moment and retrieving them in case of theft. Sherlock is invisible. It provides an unique identification of the bicycle and is trouble free. The device is very small and flexible, so it can be installed inside the frame of the bike, so to be less vulnerable to impacts and atmospheric factors and difficult to find. Thanks to Sherlock mobile app, customers can create a passport of the bicycle, associating univocally the bicycle to the owner. The customer receives a turnkey solution, including a device that is easy to install, an Internet data plan for Bulgaria and EU for 24 months, and the localization service on a dedicated mobile app.