Same, have a boox, getting a second boox, and really wish I had a better option to track location across devices. KOReader is a nice reader experience, but browsing books sucks. I use a blend of moon reader and the built in app depending on my mood, but neither feels as good as maple reader on my iPad, and nothing I’ve found can really sync my location.
On kindle, if you tap the middle of the screen, then click the little Aa up top, you get formatting options. On reflowable formats, you can go to the more tab and uncheck the animation button. On ones that are fixed pages, it should be one of the only options.