Field service companies are facing upheavals in the management of their day-to-day business, which is leading their customers to be more and more demanding. To meet these new expectations and deliver a better service, it is necessary to reorganise, particularly by adapting to digital technologies. This means, in part, improving the conditions of mobile technicians, through the deployment of mobile solutions adapted to their uses and constraints. The need is for both a hardware and a software solution. The integration of a new tool into an information system requires the expertise of a specialised company. A co-development process is therefore needed to take advantage of all the qualities of an on-site service company and an IS integrator specialising in UX/UI. This book offers an outline of the mutual growth opportunities that can exist between these two types of organisations.