The audio-to-score framework consists of two separate stages: preprocessing and alignment. The alignment is commonly solved through offline dynamic time warping (DTW), which is a method to find the path over the distortion matrix with the minimum cost to determine the relation between the performance and the musical score times. In this work we propose a parallel online DTW solution based on a client-server architecture. The current version of the application has been implemented for multi-core architectures (86, 64 and ARM), thus covering either powerful systems or mobile devices. An extensive experimentation has been conducted to validate the software. The experiments also show that our framework allows to achieve a good score alignment within the real-time window using parallel computing techniques.