Notes is a notetaking app developed by Apple Inc provided on the company's iOS, iPadOS, visionOS, and macOS operating systems, the latter starting with OS X Mountain Lion.

It functions as a service for making short text notes, which can be synchronized between devices using Apple's iCloud service.

The application uses a similar interface on iOS and macOS, with a non-textured paper background for notes and light yellow icons, suggesting pencil or crayon.

Until 2013, both applications used a strongly skeuomorphic interface, with a lined, textured paper design; the Mountain Lion version placed this inside a leather folder. This design was replaced in OS X Mavericks and iOS 7.

In iOS 7, as with all other default apps, Notes was redesigned, losing the notepad-like UI in the process.

Starting with iOS 9, Notes received a significant functional overhaul: iCloud sync (instead of IMAP; in-line with the OS X El Capitan version), the ability to create sketches (and later, support for Apple Pencil), advanced text formatting options, several styles of lists, rich web and map link previews, support for more file type attachments, a corresponding dedicated attachment browser and a system share extension point for saving web links, images, etc.

As of iOS 9.3, individual notes can be password-protected (with the ability to use Touch ID to unlock all notes on compatible devices), however, only one password can be set for all notes locked henceforth. The password syncs across compatible devices.

In iOS 10, Notes now has a collaboration feature for many people to work on a note at the same time.