Kindle uses .azw and .azw3 files. The full version natively supports AZW, but for best results, rename the extension to .mobi or use the File > Open All Ebook Types filter. Note that AZW3 (KF8) has a different structure; Mobi Info Edit works best with the older MOBI7 standard.
The workflow for creating a transit program generally follows these steps: Mobi Info Edit Full Version
"Changes don't appear on my Kindle after USB transfer." Solution: After editing, you must delete the old file from the Kindle, eject the device, restart the Kindle (hold power for 20 seconds), then re-copy the edited MOBI. Kindle caches metadata aggressively. Kindle uses