Windows Phone is basically the same thing, just not overpriced. Not sure what you mean "play nice with an iPad". If basic file transfer, anything should be fine.
Which Android? Decide what screen size you want, whether you require a physical keyboard, whether it'll see use as a global phone, whether you might wish to use an extended battery sometime. If you're the impatient type, be sure to get one with zero lag time when responding to commands (dental work ain't cheap). If you want to reduce attack surface, choose one that can be easily rooted (so then you can remove/disable useless cruft). Quad-core, 4G etc, are all technologies to enable game-playing, soap-opera streaming, and other wastes of time; since you don't plan to engage in those, why pay the cost of higher power consumption?” from K
The best thing about an IPhone is the user friendliness of the applications, I have been using an IPhone 4 for more than a year, and it has never crashed, not even once. While the Android devices are cheaper, and they promise you free applications on the Android market, but these applications are not even half as good as the applications available on the iTunes / app store. I have used both the Android and the Apple OS devices, and I personally feel that the IPhone is far ahead of rest of the lot.” Damodhar
The idea that things are going to revolve around the desktop was very popular a decade or so ago, but things have changed since. The prevailing thinking today is that your content is going to be stored server-side (on premises or "in the cloud", but on a server nevertheless), and you can use multiple client devices (desktops, laptops, phones, tablets) to view it and add to it. Mainstream vendors are no longer concerned with things talking to desktops or Outlook; instead, they make things that talk to servers. Incidentally, the desktop itself is increasingly used to access server-based content, too...
I don't know how comfortable you are with this, pardon the management-speak, "new connectivity paradigm", but that's where the mainstream is. Whether you want to rejoin it is entirely up to you.
As to the iCloud, I am skeptical. Apple is not known for being able to make scalable online applications, so I thought it best to stay away from iCloud. If you're interested, here's the setup I came up with for myself. My mail (with my own domain name) and calendar are hosted on Yahoo! Small Business (before you ask, I settled on it back in 2004, before there ever were such things as Gmail and Google Calendar; plus, unlike Gmail, Yahoo! Small Business doesn't have a cap on storage space). I use a small army of devices (currently, two Windows desktops, three Windows laptops, one Linux desktop and an iPhone) to access it all. If I wanted to add a Mac or a tablet into the mix, it can be done in minutes.
I don't know if you're comfortable with this sort of "server-centric" setup, but in my opinion ("opinion" being the operative word), this is the only way to make your content accessible to multiple devices running on multiple platforms. Reliance on the desktop just isn't going to get you there... “ Nick
Jeff Snyder’s SecurityRecruiter.com Security Recruiter Blog