I had a hard time finding this info, so thought I would post it here.
Say you have a .mobi file that you’ve legitimately obtained through some approach other than the Kindle Store. (Like the .mobi files in the Hugo Packet.) Say you want to read that file on your Kindle or in the Kindle app on your computer or a mobile device. (I’m assuming you already have a Kindle account, whether or not you have a physical Kindle device.) And say you want your highlights and notes to be synced across all those places.
To do that:
- In a web browser, go to the “Manage Your Content and Devices” page.
- Find one of your devices that you want to send the .mobi file to.
- Click the “…” button for that device, in the left-side “Actions” column.
- Copy the email address shown for that device.
- Send email to that address, with the .mobi file as an attachment. (Subject line can be anything you want.)
After a few minutes, the .mobi file that you sent becomes available for download to any of your devices. After you download it, Amazon starts syncing your last-read position and your highlights (and notes, I think) across devices.