The conventions and design patterns that have the biggest impact on adaptation can be grouped into four key areas.

• Navigation. Many iOS and macOS apps organize data in similar ways, but they use different controls and visual indicators to help people understand and navigate through the data.
• User input and interactions. Although both iPad and Mac accept user input from a range of devices — such as the Multi-Touch display, keyboard, mouse, and trackpad — touch interactions inform iOS conventions, whereas keyboard and mouse interactions originated the conventions for macOS.
• Menus. Mac users are familiar with the persistent menu bar and expect to find all app commands in menu bar menus. iOS, on the other hand, doesn’t have a persistent menu bar, and iOS users expect to find app commands in the app’s UI.
• Content scaling. Text in the macOS version of an iPad app looks the same as it does in iOS because SF fonts are available on both platforms. However, the baseline font size in iOS is 17 pt, whereas the most common font size in macOS is 13 pt. To ensure that your text and interface elements are consistent with the macOS display environment, iOS views automatically scale down to 77%.