At the top of the screen when you press Menu, the amount of free space and the time are displayed. Obviously it knows where I live.
Synchronization between Kindles will only work with content purchased from Amazon, not public domain books you have put on your Kindle.
The text-to-speech feature is not at all bad for occasional listening. You can read along with it and the page turns automatically along with the voice. What I have learned from reading along with its text-to-speech feature, is that the reading is at its most understandable if punctuated properly. When it is reading headings with no punctuation, it just races right into the next line of text. However, it would still be great for continuing to listen to something for a brief while when you needed your eyes to be elsewhere. Not a substitute for a regular audio book, though, I assure you. It defaults to the male voice, but since I am currently reading Silent in the Grave (Deanna Raybourn) written as if a woman were telling the story, I switched to the female voice. This seemed only logical.
Most of the button pushes are toggles. In other words, if you press Menu and want to get out of it, press Menu again.
People complained that the K1 buttons were too easy to press. Of course, this was because they ran along both sides, leaving little space where you could handle it safely without inadvertent page turns. Now some are saying that the new, smaller page turn buttons are hard to press. Not really. They need to be pressed on the side closest to the screen rather than the outside edge. Apparently this is a further attempt to prevent doing it accidentally. But trust me; the buttons work easily. With my hand problems, I would feel right away if something were more difficult.
If you want to read a description of one of your purchased books, when its title is underlined, move the 5-way to the right and it brings up a menu which includes Book Description. Selecting that will bring to you to the Kindle store and the description. Don't press that Buy button again!