IES Cities is the last iteration in a chain of inter-related projects promoting user-centric and user-provided mobile services that exploit open data and user-supplied data. The technical components and achievements of several former European projects will be integrated to assemble an open Linked Data apps-enabling technological platform. Such platform will be deployed in different cities across Europe, allowing the citizens to produce and consume internet-based services (apps) based on their own and external open data related to the cities. Something specially remarkable about IES Cities is that no project before has considered so much the extent of the impact that the users may have on improving the open data in which services are usually based. The user-centred approach is a must for the success of the project. The target groups of the project will be citizens, SMEs, ICT-Developing companies and public administration. IES Cities will provide a user-centric urban apps enabling platform for users in four cities across Europe. Each city will initially test the functionalities of the platform with completely independent services, different at each location, in order to allow the cities and their citizens covering different needs under a common platform. Users will be able to continuously enrich the consumed services with their own data and to have a voice in the proposal and selection of new services to be developed. The set of pre-defined urban services defined is spefic to the cities where they will be deployed since not all cities count with the same data and the same needs for their citizens. These services will target different strategic topics in a city such as mobility, environment, health, culture, knowledge of the cities and so on. The project comprises partners from five different European countries who will deploy and validate the integrated open platform for enabling Linked Data urban apps in cities from three different countries in Europe. The cities involved will be Zaragoza (ES), Bristol (UK), Rovereto (IT) and Majadahonda (ES).