A keyboard for the iPad is useful because it makes typing more efficient and comfortable. For longer texts or documents, a physical keyboard is usually faster and more precise than typing on the touchscreen.

The use of a keyboard promotes a better hand posture, reduces fatigue during longer writing sessions and thus reduces the load on the hands. In addition, navigating and editing texts is much easier by using keyboard shortcuts.

Yes, a keyboard can interfere with the use of iPad in certain applications, especially if they are heavily dependent on touch gestures. It can be cumbersome to switch between keyboard and touchscreen, which can interfere with the workflow. Therefore, it is advantageous if the keyboard has a touchpad.

Apple's iPad keyboards are charged via the Smart Connectors. Other iPad keyboard cases use batteries.