Most taxi services don't have apps, or have apps that are just the equivalent of phoning the dispatcher.

So the solution would be to add better apps, rather than skirting safety regulations and undermining workers' rights.

Yes, and in a city such as Berlin where the taxi supply is not artificially restricted through a mediallion system, and sensible safety and labour laws prevail to the extent that Uber is not even able to operate, an app like MyTaxi functions just about as well as "ride sharing" apps in my experience (though it trails in significant innovations such as UberPool / LyftLine).