Oliver Peters asks himself this question in his blog entry
Trusting Apple Displays?. Gone (at least for the time being) seem to be the days of gathering in a room around a reference monitor for final grading. In home office times, final gradings are sent over the internet for approval and then - well - viewed on which device with which monitor and which setting? - viewed.
Oliver Peters sees iPhones and iPads as the current de facto screen standard for consumer devices. In his opinion, the advantages lie in a largely homogeneous colour representation. But here, too, there are many pitfalls. How to avoid them can also be read at Digitalfilms.