Motor impairments seems to play an important role in neurodevelopmental disorders such as autism spectrum disorders (ASD). Early detection of motor abnormalities during first years of life, may give important information regarding whether a child may receive a later diagnosis of Autism: for this reason an objective assessment of motor performance is crucial. While there are several technological solutions suitable to this end, they often require highly structured environments. In this work we propose the use of a magneto-inertial platform to study early motor performance between 12-36 months of age suitable to be used in non-structured environment.