I know that the topic of "iPad Pro vs Surface Pro 4" has been beaten somewhat to death, but I figured I would share my take on it to help others trying to make the same decision process (without going into specs, since everyone knows what those are). First off, some background... I'm a software engineer by trade, and my hobbies include electronic music production/DJ work, and photography. For personal machines, I have a lovely 2013 Mac Pro on my desk with two 27" 4K monitors, and a 15" Macbook Pro (late-2013). I've also got an iPhone 6s plus and an iPad Air (1st generation). Last January, curiosity got the best of me and I purchased a Surface Pro 3. I have to say, it wasn't love at first sight. I found Windows 8.1 to be clunky, and the floppy keyboard "not quite a laptop but not quite a desktop" model took some time to get used to. I stuck it out though, and eventually found that I wasn't really using my iPad Air (1st generation) anymore at all. It was pretty neat to have that bigger screen, and have access to full Windows desktop apps. When Windows 10 came out, the experience became much better. Windows 10 is actually the first windows version in a long time that I actually like! In the fall when the Surface Pro 4 came out, I decided to give the Pro 3 to my dad, and picked up a 4 for myself. It's a lovely little device, the new Type Cover 4 is so much better than the previous version, I'd say it's very close to using a Macbook's touch pad and keyboard (smaller of course). There are some issues with bugs and Windows 10 that MS has been slowly resolving, such as freezing on wake, issues keeping the devices asleep, etc. Moving on to the iPad Pro... Again, curiosity got the best of me, so I decided to pick one up, figuring that I could always return it after 14-days if I don't like it. After a few days, I love it. I'm realizing that my usage pattern of the Surface Pro 4 was not much of a "laptop replacement", but more as an iPad replacement. I love the bigger screen of the Surface, and the iPad Pro's screen is even bigger yet. I've mostly been using the Surface for web browsing, e-mail, and as a travel machine. The iPad Pro is actually a bit better in these regards (for me). I can even use the app "astropad" and replace my lightly used Wacom tablet for photo editing, which is great (I like consolidating devices as much as I can). The argument about it running a "phone OS" is actually a plus for me. First off, the App store for Windows touch apps is nothing like that of iOS - you really are stuck with using full on desktop apps (some of which aren't touch friendly), or little cheap games and the like. Second, I really did miss being tied into the Apple ecosystem - iMessage, iCloud integration, etc. And having a phone OS means you get the niceness of battery management that works, instant on, and REAL touch integration. Microsoft is claiming that the iPad Pro is a companion device, and I'd mostly agree with that - and I'm OK with that. Unless your usage is just general computing (web, email, basic office docs, simple photo and movie editing), you probably will need another machine. If you don't do much portable computing, this might mean a desktop - the iPad Pro is certainly a great travel machine if you don't need to do heavy lifting. The Surface Pro can certainly be your full time only machine - with some caveats. The ergonomics of the Surface don't compare to that of a 15" Macbook Pro, at all. If I need to do "real work" and be portable, I'd grab my MBP over the Surface, any time. The Surface is far too cramped for me to do software development for any length of time. Of course, unlike the iPad Pro, you can use the nice dock that's available and with one cable you can hook up a keyboard, mouse, monitor and have a desktop machine. So in any case, both great devices... you should evaluate your own usage patterns carefully before buying. Consider carefully how important the Apple ecosystem is to you. Myself, I've decided to keep the iPad Pro and sell my Surface Pro 4, because it just fits my own usage a bit better.