Personally i do not think that there is a need for separate smart city blockchain or coin all we need is smart contacts, dApps and all applications using eth blockchain and we can use any or all top 20 coins as the official coin, when this approach will be applied only then we will be able to spread this tech across the cities around the world. So that more and more cities can become truly smart cities.
Majority of work that goes into City Chain and the Smart City Platform, will be compatible with Bitcoin-based coins. Majority of the development is also ported to Blockcore, which is a project that enables Bitcoin-based (both PoW and PoS) blockchains to be launched and run using .NET Core and C#.
https://www.blockcore.net/There are many services that most people take for granted that are delivered by municipalities and states. While all of them is not required for a city to operate, there are some that we want to develop and have available for private communities and cities, such as Liberstad. Smart Contracts, dApps and distributed compute and storage is an important part of that, but also having it in a unified and user friendly manner is important. So that is part of what we're working on =)