iOS 8 (currently 8.1, to be precise) is, from what my memory can recall, the most bug ridden iOS I've ever used. And I've used almost all of them.
The most severe of those bugs - the one that causes apps to randomly fail back to the Home screen, is actually making me use my devices (iPad Mini Retina and iPhone 6 Plus) far less than I ever normally would.
For example, I use Day One to capture my thoughts during the day. Now I don't, because it'll fail to launch first time virtually every time, so now it's become a much less useful app - thanks, I suspect, to iOS 8, rather than any failing on the part of the app developer.
It's such a common problem and not app specific - a lot of my every day apps are doing this. I'm in the process of discussing this with the Day One developer to try and get to the bottom of it. I suspect it's the usual iCloud Drive issue.
So, rather than being able to rely on the fairly critical requirement of an app actually starting up, I just think "I'll do it later" because I don't have time to go through the start, crash, start, crash, start, crash, reboot, start, crash etc cycle, and, of course, I then forget, so it doesn't get done.
Another example (which led to me writing this): At breakfast, I like reading Bike Magazine on my iPad. It's supposed to be a nice relaxing way to start the day, but instead turns into a major source of frustration as, rather than enjoying the experience of reading about having fun on motorcycles, I'm trying to work out why another sodding app (not the apps fault, but still) is not working properly.
Most iOS bugs in the past have just been an irritant, but this is fundamentally screwing with how I wish to (and have a right to expect to be able to) use my very expensive devices.
I'm not using some truly excellent apps because Apple have been unable to supply me with a stable platform on which to use them.
I can't help feeling this would never have happened if Mr Jobs was still with us.