Well, based on those definitions, I'd say neither are hybrids but rather tablets, further reinforced by the fact that neither include keyboards but are rather optional accessories. I'd consider devices like the Surface Book, Asus Transformers, or Lenovo Yoga models as tour hybrids.
Regardless of the their defined classifications, both occupy overlapping segments, if not the same target customer. Specifically, I'd wager that anyone considering puchasing one will at least take a look at the viability of the other. I think the SP4 skews more to the traditional productivity side of the argument, more so than th iPP but that is bound to change
IF developers find the iPP a viable tool for more robust productivity tools.
And on a related note, look what I broke down and decided to buy today.
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