The icon marker is part of the spatial annotation system. Use icon markers to help annotate real world objects.

Principles
Contextual: Icon markers are locked to real world objects or points.
Concise: Icon markers are abbreviated visual indicators of a spatial anchor.
Usage & Placement
An icon marker is an icon-button-like UI element that marks objects of interest in the user's environment. The icon marker is a type of spatial marker, used for spatial anchoring.
Do
Don't
Any other Jetpack Compose Glimmer component can be paired with a marker for greater clarification or insight on the user's surroundings.
Do
Don't
Content and labels can be placed at different orientations. Markers, and any attached UI, should behave as spatial UI, meaning the actual distance of the marked object should be reflected in the size of the UI, using a constant angular DP size.
Clearly define markers to avoid visual clutter, and limit the number of markers
within view. If multiple markers are needed, cluster them together as one,
more-prominent marker that can be progressively viewed.
States
The icon marker is very similar to an icon button. The main difference is that rather than a disabled state, it has a non-interactive state.
Annotate the physical world with the non-interactive state, like marking a point
of interest.
If there is more information that might be available, you can use the interactive state that has a button affordance. If the user taps the icon marker, a Glimmer card with more information is displayed.
Anatomy
The icon marker itself is a small icon button UI element with padding allowing for a fixed UI alignment and orientation. The icon marker can also use a large or small dot instead of an icon. The interactive state includes a visual affordance to denote the button state.

Padding
Horizontal and vertically positioned UI have a medium padding, while diagonally paired elements have a 0 dp default padding.

Alignment
UI elements can be positioned at horizontal, vertical, or diagonal points.

Orientation
Content should billboard toward the user, while respecting gravity to make the content feel organized.
Customization
To keep a consistent visual affordance, avoid customizing icon markers. However, you can customize the orientation and alignment of the attached UI elements.
| Properties | Customization | Defaults |
|---|---|---|
| Icon | Yes | Large dot, small dot, Icon |
| Padding | No | Top Center, Center Right, Bottom Center, Center Left = medium Top Left, Top Right, Bottom Right, Bottom Left = 0 dp |
| Alignment | Yes | TopLeft, TopCenter, TopRight, CenterLeft, CenterRight, BottomLeft, BottomCenter, BottomRight |
| Orientation | Yes | RotateToLookAtUser: The dot billboards towards the user no matter angle of rotation. |