Kobo natively supports Instapaper, and all of the content shows up in the Articles section. Sadly, the Amazon Kindle also supports it, but the execution sucks. Instapaper, comes with Kindle integration built in—but only if you pay for the premium service, which is $6 a month. Deleting the articles is also difficult to do, as the Kindle does not officially support web articles. However, I wish Kindle had its own read-it-later service, rather than relying on these janky workarounds.