Re: This is probably about the OS
Surely the only conceivable reason can be availability of security updates, and even that's a bit tenuous. While not a direct user of Salesforce, my understanding is that it is basically a website that accesses a database and renders dashboard reports - hardly something that demands the most up to date phone with all the bells and whistles, when all it needs is an up to date browser renderer, and a decently coded website that will muck around with the layout for different screen sizes - something baked in to HTML5.