Amazon released an update for its Kindle iOS app last Tuesday, and it's a pretty useless one.
According to the changelog, some time in the next few weeks we will be able to enable a Siri shortcut to open our most recently read ebook (iOS 12 only). This shortcut will activated in the Siri menu under settings before we can use it, but once it is you will be able to tell Siri to open the ebook so you can continue reading.
... Is that all?
Don't get me wrong, I can appreciate the value of voice commands. My issue here is that this one command is completely useless without other commands like next/previous page, "open library", "open Kindle title", "add bookmark", etc.
Without enough commands to enable real hands-free use, what Amazon is doing here really only amounts to a gimmick and not a useful feature. They might as not have bothered, and saved their energies for another feature.