Now Safari users on Apple iOS devices can take advantage of the Kindle e-book app as a read-it-later solution, thanks to the latest update from earlier this week.
You access the feature via the share sheet in the browser (that's the upload icon). Oddly, when I tried it the document appeared on my Android phone before it finally synced to my iPhone.
On upload, you can change the title and author, as well as choose whether you want it to go in your Kindle library for cross-device sync, or just send it to a particular device.