Transfering small tidbits of information from Mac to iPhone You found that the book you were going to order online is in stock at your neighborhood bookstore (it's a near fantasy for your neighborhood bookstore to stock a book you actually want, but it's just an example! It applies for any kind of shopping list).

You copy the ISBN from your desktop browser, but rather than copy it on paper, you enter it in tool X. Tool X will make that number available on your iPhone so that it's handy when you ask for help at the bookstore.

Does Apple produce such a tool X? You could use Google Keep, or you could email yourself and pick up the mail from your phone, but I'm wondering if Apple has a native application for this use-case in its eco-system.
There's multiple options when you're using the same iCloud account on your Mac as on your phone:


Add it to a Notes note
Send it to yourself as a Message
Add it as a reminder in Reminders
Add it as an appointment in Calendar
Use Universal Clipboard to paste the content on your iPhone that you have copied on your Mac