Sheets are full-screen views you can use for tasks. Sheets overlay the current context by sliding in from the right of the screen onto a full-screen view. When users complete the task, sheets slide right and disappear, and users return to their location on the screen.
Users can't swipe left or right on the content area of a sheet to navigate back, but they can peek at the previous screen by dragging their finger to the right. This approach helps prevent users from dismissing the sheet accidentally.
You need to initiate a task from more than one place.
You need to initiate temporary tasks, such as showing a contact in an app other than the Contacts app.
You have tasks that require users to enter information in several fields, such as creating a new message or meeting.
Don't use when
You have simple tasks or tasks that don't require navigation.
Include a title bar with action buttons at the top of the sheet. This helps prevent users from submitting information accidentally by providing physical space between the action buttons from the touch screen keyboard.
Disable positive actions until users enter the required information.
Put positive actions, such as Send, Share, and Save, as buttons in a title bar at the top-right corner of the screen.
Put destructive actions, such as Cancel, Close, and Back, at the top-left corner of the screen.