I'm on Android not iOS. But I use the Pinboard app. When I want to save a webpage, I use the "share link" menu [under the browser hamburger menu] to send it to the Pinboard app.
Definitely check out Pinkt for Pinboard [0]. It is a rather new Android Client for Pinboard which is actively maintained and has quite a nice UI - and besides that it is OSS.
[0]: https://play.google.com/store/apps/details?id=com.fibelatti....