Which Apple device is primarily designed for portable use and includes a touchscreen?

The iPad is primarily designed for portable use and features a touchscreen interface, making it a versatile device for a wide range of activities, including browsing the web, watching videos, playing games, and using productivity applications. Its lightweight design and compact form factor allow it to be easily carried and used on the go. The touchscreen is a significant aspect of the iPad, as it enhances user interaction, allowing for gestures and direct manipulation of applications and content, which is a core part of its usability.

The MacBook, while portable, does not primarily feature a touchscreen and is designed more for traditional laptop use with a keyboard and trackpad interface. The Apple Watch is also portable but is a smartwatch designed for quick interactions and health monitoring rather than a full touchscreen experience found on larger devices. The iMac, on the other hand, is a desktop computer intended for stationary use and does not have the portability or touchscreen capabilities that define the iPad.