This is a natural convergence two trends: [1] that HTTP APIs operated by to most webapps/services do not have feature parity with their actual website, even if

This is a natural convergence two trends: [1] that HTTP APIs operated by to most webapps/services do not have feature parity with their actual website, even if only in the sense that a third-party client has to implement a custom controller/view logic whereas a website already provides that courtesy of the first-party; [2] and that the Web Platform (previously known as "those random javascript globals under 'window'") has more and more 'hooks' to functionality to what's traditionally implemented by a modern desktop/mobile OS.