Data Security in Day to Day Life and Its Consequences: Case Study

People of Metro/Smart cities use multiple mobile application to ease up their life. Problem statement is that all different mobile Apps are mutually exclusive. Private Data (1) may be a public data for Application A i.e. Flat Number of a society, But Application B can reveal other Private Data (2) on basis on this Private Data (1) This cycle goes on and ultimately Name, Phone Number, Email ID, Flat Number, Meter Number, Electricity Consumption, everything is leaked.