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Intelligent speed adaptation (ISA) is a promising technology to dynamically limit vehicles speed. Indeed, it can provide the authorized speed limits values to the drivers. The interest of this kind of system is its embedded character in order to inform drivers in live. That's why it is important to implement it into a cheap and available technology like a smartphone. However, because the smartphone GPS positioning are often inaccurate, the displayed speed may be wrong. This paper presents a process to determine the speed limit values by matching a vehicle real road-network position with a map and a database. It combines a predictive model of movement in order to limit instants without informations, an In-of-Order Kalman filter which corrects the GPS measurements and takes account of variable sampling time and finally an online map-matching algorithm based on several weighting parameters. The system will be qualified of “dynamic” because it has the advantage to display short-time speed limits. Simulation results and experimental results will also be included.