Most apps are just Database front ends. Change my mind
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The other class is one where the application manages a business process, with or without people being involved. In this case the data is more saved state rather than business data. Obviously other data will be involved but if the primary purpose is managing the process then I consider this to be a counter example.
OpenOffice/libreoffice
Gcc/clang
Animated and rendered graphics
Calculators
Hardware drivers (radio, compass, metal detector, accelerometer)
Sure, apps have data storage and “frontends” for UI and computation.
We could say most databases are just backends for UI and computations.