iOS 8 on first gen iPad mini?

You could have either posted this in the iPad or iOS8 sub section. Yet you decided to post it in iPhone. Why?

Thread needs moved, but at any rate yes. iOS 8 is horrible on the original mini. I can start typing a web address and have it finished before it even starts showing up on screen. I'm can't wait for my Air 2.

If you check the iPad forum, you'll see that 8.x on a Mini 1 is something of a mixed bag, with some users saying they didn't see a huge difference over 7.x, and others reporting things like yours. Since the Mini 1 basically has the same specs as an iPad 2 and those aren't doing too well on 8 either, it's probably not a great upgrade for those devices.

That said, since you can't go back down to 7.x, try a clean install (don't restore from backup, you can always do that later). Download only the bare minimum of apps, don't sync anything over immediately, and see if the device runs any better. If it does, you may have to pick & choose what to put back onto it.

If it doesn't, Mini 2's have dropped in price, and Mini 2 refurbs are a terrific deal right now. (That's what I opted to do; my Mini 1 was already having issues on 7.1.2, so no way was I taking it up to 8.)

Good luck!

Seems to work fine on my Mini, but I don't use it a ton. Mostly rely on my iPhone 5 or rMBP.