The Smart City concept is a very recent one, which, nevertheless, has already implemented in several cities around the world (for example, Dubai, Moscow, Paris). The satisfactory results are encouraging more and more cities to experiment with this concept; given that the normal city of the future will be the smart city, regardless of its size and location. We have noticed during November 2018 Sétif start-ups fair, in Algeria, the strong desire of local authorities and investors to shift to a smart management of their city (Elmoudjahid, 2019). In this article we will study the transition of an ordinary city into a smart city, whatever its socio-economic environment. The concept of a smart city will be presented, in the first instance, then we will examine various examples of cities in view of transitioning to smart city, so as to propose an application at low-cost based essentially on the collaboration of the inhabitants (which we will call "smart Citizen-centred city"), this way we will pass over the lack of developed systems benefitting from open data, sensor networks, etc. Because of this, we have selected the theme "intelligent transport", presenting a simple transport application in the Wilaya of Sétif, which will depend on the connected people.