A more useful discussion would be, what kind of apps should be paid? and what kind should be free? In my opinion paid apps/services have to meet a few criteria:

A more useful discussion would be, what kind of apps should be paid? and what kind should be free? In my opinion paid apps/services have to meet a few criteria: 1. substantially better than free alternatives 2. deliver significant value at limited (user) scale 3. not built on open source technologies w/restrictive licensing For broad consumer-services, those 3 criteria actually limit the universe of services significantly.