Cool discussion you have guys! As a Software Developer myself I find to be in between all of you
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I can't talk about Chromebooks as I don't have it. There a lot of iOS apps so yes in theory you can find more apps in iOS that suits your need compared to Android tablet. I agree with that, but the lack of files managements for me hinders any iOS app and as a result I cannot be productive the way I am using computer.
People are saying you have to get to used to iOS. Um no. I won't change my workflow to accommodate to iOS. Apple will have to develop iOS to accommodate to the needs of its end users. Until this happens people like me (and others in this thread) would never see an iPad Pro as anything more than media consumption device and digital notebook.
As a Software Engineer actually I would have never used iPad for university. No change in hell. That thing cannot do 10 % of what I needed as a student. I cannot write Java code, I cannot 3D studio or Solid works or Autocad, I cannot UML diagrams, I cannot run semantic web applications, I cannot create SQL databases. So just like the iPad helps some (you mentioned great cases) it does not help at all for Software Developers. Same if I have to create a lot of Word documents or powerpoint. iOS sucks with text editing and typing in general. It's PITA. Like seriously. I get crazy trying to edit something in iOS. Apple really needs to rethink this because I cannot use this device even for simple emails or chats. I spent more time wondering on who exactly came up with this awful solution than actually doing what I am supposed to do.
It's more than that. There are cases that are not covered by iPad like batch processing of raw photos, Software Development, Microsoft office suite usage in general.
As for the people that say that they cannot edit video without Lumafusion or cannot produce music without some iOS app. Windows, macOS and Linux exists way more than iOS. There are apps for those kind of stuff for those operating system as well. It's OK that you have preference over the iOS apps. There are people that are on the opposite end though. They prefer their desktop apps because they find them more useful and more productive. For me productivity means being able to do as fast as possible the things I need to do. That is not the case when it comes to iPad. Quite often the drawbacks of iOS itself slow me down. Every time I have to open a file in one app and then share it in another instead of just going directly to the files system and open the file in the app I want it is a waste of time for me. Every time I have to delete a sentence I have written and rewrite it again because I cannot edit it is a waste of time. Every time I have to connect my iPad to the computer via iTunes and start working it (seriously dislike iTunes) is a waste of time for me.
To not waste my time I obviously don't use the iPad for productivity that much. This way I can minimize those annoying cases. And I just don't use the iPad for typing.
Yes there are things that I would do on iPad - writing down. I love to use it as a digital notebook and it's not something most laptops currently can offer me. However that's the main thing I use the iPad for. I don't see it as a pro device because unfortunately iOS does not cover my case. And for people like me unfortunately iOS is like years behind on what I need. This does not mean that there are not people that could be near 100 % productive on iPad. I respect that, but people should also accept iOS drawbacks and understand that for certain people those are deal breakers.