For all intents and purposes, a laptop computer and a smart phone are one. This is, for example, evidenced by the fact we run general purpose "applications" on them (not defined ahead of time), including a most general app of them all (a web browser).
For other device types you bring up, I would go with a very similar distinction: when you can run an open ended app platform like a browser, why not be able to install non-browser based applications as well? Why require going through a vendor to do that?