Along those lines I think the reddit mobile site is particularly bad. Every action takes ages so you think it didn't "take". Then you press Back nav or buttons. Then, in the last moment just before your fingers hit the screen, it changes to the "page" you requested, and you navigate back to your original page. Frustratingly, the SPA navigation doesn't give feedback, like plain page-based navigation would. Makes you want to throw your smartphone out of the window.
The irony being that if you switch to desktop mode on Reddit, it's much, much faster and totally usable, a small number of stylesheeet tweaks would make it great.
Reddit's mobile version is a travesty of engineering, a total waste of time and money.
I would have personally fired the engineer who came to me with that thing, I don't understand why they keep pushing it.
