I’ll chime in...
With Android, it’s a pretty mature OS, but it’s a bit separated, for instance with a Pixel you get the naked experience, it also means very fast performance and updates, but you don’t get as many features, the new Pixel 2 XL for instance has been reviewed as having a lower quality screen then the iPhone and Note 8, I am yet to see one personally though.
Then you have all the Android manufactures, they offer everything you could think off and at all levels, but then you don’t have the same updates all the time, so you may not get that security bug fix you want, Samsung are not the best with updates, but arguably make amongst the best hardware.
Now you also have apps that work fine, aren’t quite as smooth or optimised.
With Apple you get great app optimisation, quality usually, but they are expensive. You also get iMessage if you don’t use WhatsApp, and an easier to use interface.
You also get integration as you said of its devices.
It’s a tough choice, I like the Apple Watch and the iPad Pro, I own both, but I had a play it’s the Note 8 recently and it was stunning, I would consider it if it worked with the Apple Watch, I’m not sure it will fully though and theirs an example of that closed system.
But the price of the Note 8 has dropped already, the idea of the possibility in a few months of getting one for say £650 to £700 is sooooooooooo tempting..
But their does seem to have been a change at Apple over the last few years, iOS has got more and more buggy, their is no excuse for it when Apple design and own ALL the hardware it runs on, and they have ludicrous amounts of money for resources, programmers etc. It’s a very shoddy place to be.
Their computers have also suffered with no updates and price increases.
Their really are pros and cons with both, I’ve had both Android and iOS, Windows and Mac. These days I also look a bit more for value for money, and again that Note 8....
You might want to check out the Gear S3 as an alternative to Apple Watch. After having AW for 2 years and wearing very day, I now much prefer the Gear S3.