You are a teacher. Your view of this topic is a bit skewed I think. Not trying to take a way the value of what you do which is a very important career, but its hardly representative of what business users need. I work for a global software company and travel the world interacting with our customers... both commercial companies and government agencies.
Aren't our experiences with devices skewed by factors such as our choice of profession?
That's my point. The value of 2-in-1 convertibles (and the outright dismissal of iPads as a legitimate productivity machine) seems to revolve very heavily around their ability to run legacy desktop software (namely Excel, but also some more specialise programs), and using them more as PCs than tablets.
Yes, the needs of business users matter, but they don't make up the entirety of users' needs.
I bought a Surface Pro with my own funds to replace my company provided enterprise grade laptop, and my Mac & iPad. In my experience, everything you said there is completely incorrect. I would certainly not have done that if it didn't give me tremendous value.
That just goes to show that different people use different products differently, and derive varying amounts of utility from them.
I myself used my own money to install an Apple TV in my classroom (I have 2 at my desk) and an iPad Pro, precisely because they give me tremendous value for the work that I do. I didn't get a windows convertible because they didn't fit my needs very well.
"form factor ill suited for use on any surface other than a table" - completely incorrect. I use the Surface Pro on planes, in my lap sitting on the sofa, at my desk (connected to a dock w/ 4k display and peripherals), by the pool, in my truck, sitting in the airport. I've used it with and without its keyboard in all these settings and more. The Surface Pro (and its clones) is physically different than a clamshell laptop, but no more or less usable in any scenario its needed.
I find there is more to a tablet than just the form factor. My iPad Pro is thinner, lighter, runs optimised tablet apps and I am probably just more comfortable interacting with iOS over macOS or Windows.
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On a side note, can you recommend any decent pdf annotating apps for windows? That's the one issue I still have with my school-issued HP convertible. If it isn't too expensive, I could probably make a case for my school's IT dept to make a bulk purchase. On the iPad, it's largely a solved issue with Notability and PDF expert.
"isn't designed for on the move computing the same way iOS is" - agree that its not the same way as iOS. From my perspective, I'm so glad that's the case. I don't want to have to learn and deal with gimped versions of all the software I use. My guess is that you have never used one of these long enough to learn how to use it... it takes time to learn a new OS... keyboard shortcuts, gestures, etc.. Windows 10 compares more to MacOS than iOS. Your needs are served with (your words) big iPhone. For many information workers (me included), a lot more function than a big iPhone is needed. I am "on the move" around the world... you are "on the move" around the school. For my uses, I'm able to move around with it quite easily. In fact, if any use includes a physical keyboard, the Surface Pro is much more stable and portable than an iPad with the hokey keyboard afterthought. The kickstand gives such great versatility.
I have a keys-to-go Logitech keyboard for times when I need to do heavy typing on my iPad, but by and large, I get by just fine on my iPad Pro.
Just the other day, I was at a workshop and needed to create a sample lesson plan using some provided material. I used my iPad to scan them into pdf documents and annotated on them using my Apple Pencil, then presented from it using the vga adaptor.
I guess you are right in that I have used my iPad for so long that I have largely gotten so used to its strengths (and resolved whatever shortcomings I may have had with it), to the point where using a desktop OS now seems more archaic and cumbersome in comparison.
Everyone's needs are different... glad the iPad works for you. But for a vast number of people, that's simply not the case.
I question just how "vast" this group of people is, or if we are simply looking at a small but extremely vocal group of users here at Macrumours skewing the numbers and making them seem more numerous than they really are. As it stands, the Surface Pro isn't really selling in huge quantities, which seems to suggest that the concept of a 2-in-1 convertible is more of a niche product category.
Not saying that there aren't groups of people who would legitimately benefit from a product like the Surface Pro. Just means that it's ultimately still a niche market that Apple has made a conscious decision not to address.