Usability of an interactive software can be highly impacted by the delays of propagation of data and events and by its variations, i.e. latency and jitter. The problem is striking for applications involving tactile interactions or augmented reality, where the shifts between interaction and representation can make the system unusable. For as much, latency is often taken into account only during the validation phase of the software by means of a value which constitutes an acceptable limit. In this short paper, we present and discuss an alternative approach: we want to handle the latency at all phases of the life cycle of the interactive software, from specification to runtime adaptation and formal validation for certification purposes. We plan to integrate and validate these ideas into Smala, our language dedicated to the development of highly interactive and visual user interfaces.