diff --git a/CODING.md b/CODING.md
index d8b8fb4..c63f4b2 100644
--- a/CODING.md
+++ b/CODING.md
@@ -57,9 +57,8 @@ The scene, camera, and renderer objects below are representative APIs that have
 		// Set up for the next frame
 		session.requestFrame(frame => { handleFrame(frame) })
 
-		// Get the pose for the world coordinate system
-		let stageCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.STAGE)
-		let stagePose = frame.getViewPose(stageCoordinateSystem)
+		// Get the pose for the HMD or handset tracker coordinate system
+		let trackerCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.TRACKER)
 
 		// Get the pose for the head
 		let headCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.HEAD_MODEL)
@@ -126,11 +125,11 @@ You now have a couple of anchored nodes save in `anchoredNodes`, so during each
 				const anchor = frame.getAnchor(anchoredNode.anchorOffset.anchorUID)
 				// Get the offset coordinates relative to the anchor
 				let offsetCoordinates = anchoredNode.anchorOffset.getTransformedCoordinates(anchor)
-				// Now use the offset coordinates, possibly by converting to the stage coordinate system.
-				if(offsetCoordinates.coordinateSystem.type === XRCoordinateSystem.STAGE){
+				// Now use the offset coordinates, possibly by converting to the tracker coordinate system.
+				if(offsetCoordinates.coordinateSystem.type === XRCoordinateSystem.TRACKER){
 					anchoredNode.node.matrix = offsetCoordinates.poseMatrix
 				} else {
-					anchoredNode.node.matrix = offsetCoordinates.getTransformedCoordinates(stageCoordinateSystem).poseMatrix
+					anchoredNode.node.matrix = offsetCoordinates.getTransformedCoordinates(trackerCoordinateSystem).poseMatrix
 				}
 			}
 
diff --git a/examples/ar_anchors/index.html b/examples/ar_anchors/index.html
index 0ea7eea..e138d9a 100644
--- a/examples/ar_anchors/index.html
+++ b/examples/ar_anchors/index.html
@@ -58,11 +58,11 @@
 				}
 
 				// Called during construction
-				initializeStageGroup(){
-					this.stageGroup.add(new THREE.AmbientLight('#FFF', 0.2))
+				initializeScene(){
+					this.scene.add(new THREE.AmbientLight('#FFF', 0.2))
 					let directionalLight = new THREE.DirectionalLight('#FFF', 0.6)
 					directionalLight.position.set(0, 10, 0)
-					this.stageGroup.add(directionalLight)
+					this.scene.add(directionalLight)
 				}
 
 				createSceneGraphNode(){
@@ -83,8 +83,9 @@
 				}
 
 				// Called once per frame
-				updateStageGroup(frame, stageCoordinateSystem, stagePose){
-					let headCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.HEAD_MODEL)
+				updateScene(frame){
+					const headCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.HEAD_MODEL)
+					const trackerCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.TRACKER)
 
 					// Create anchors for newly anchored nodes
 					for(let anchorToAdd of this.anchorsToAdd){
@@ -102,7 +103,7 @@
 							anchorUID: anchorUID,
 							node: anchorToAdd.node
 						})
-						this.stageGroup.add(anchorToAdd.node)
+						this.scene.add(anchorToAdd.node)
 					}
 					this.anchorsToAdd = []
 					
@@ -113,7 +114,7 @@
 							console.error('Unknown anchor ID', anchoredNode.anchorId)
 						} else {
 							anchoredNode.node.matrixAutoUpdate = false
-							anchoredNode.node.matrix.fromArray(anchor.coordinates.getTransformedCoordinates(stageCoordinateSystem).poseMatrix)
+							anchoredNode.node.matrix.fromArray(anchor.coordinates.getTransformedCoordinates(trackerCoordinateSystem).poseMatrix)
 							anchoredNode.node.updateMatrixWorld(true)
 						}
 					}
diff --git a/examples/ar_simplest/index.html b/examples/ar_simplest/index.html
index bdef564..bd9251d 100644
--- a/examples/ar_simplest/index.html
+++ b/examples/ar_simplest/index.html
@@ -36,45 +36,45 @@
 		<div id="target" />
 		<script>
 			/*
-			ARSimplestExample shows how to populate the stage group that is rendered on the stage 
+			ARSimplestExample shows how to populate the content scene 
 			*/
 			class ARSimplestExample extends XRExampleBase {
 				constructor(domElement){
 					super(domElement, false)
 				}
 
-				// Called during construction to allow the app to populate this.stageGroup (a THREE.Group)
-				initializeStageGroup(){
+				// Called during construction to allow the app to populate the THREE.Scene
+				initializeScene(){
 					// Add a teapot at about eye level
-					var geometry = new THREE.TeapotBufferGeometry(0.1)
-					let materialColor = new THREE.Color()
+					const geometry = new THREE.TeapotBufferGeometry(0.1)
+					const materialColor = new THREE.Color()
 					materialColor.setRGB(1.0, 1.0, 1.0)
-					let material = new THREE.MeshLambertMaterial({
+					const material = new THREE.MeshLambertMaterial({
 						color: materialColor,
 						side: THREE.DoubleSide
 					})
-					let mesh = new THREE.Mesh(geometry, material)
+					const mesh = new THREE.Mesh(geometry, material)
 					mesh.position.set(0, 1.4, -1)
-					this.stageGroup.add(mesh)
+					this.scene.add(mesh)
 
-					// Add a box at the stage origin
-					let box = new THREE.Mesh(
+					// Add a box at the scene origin
+					const box = new THREE.Mesh(
 						new THREE.BoxBufferGeometry(0.1, 0.1, 0.1),
 						new THREE.MeshPhongMaterial({ color: '#DDFFDD' })
 					)
 					box.position.set(0, 0, 0)
-					this.stageGroup.add(box)
+					this.scene.add(box)
 
-					this.stageGroup.add(new THREE.AmbientLight('#FFF', 0.2))
-					let directionalLight = new THREE.DirectionalLight('#FFF', 0.6)
+					this.scene.add(new THREE.AmbientLight('#FFF', 0.2))
+					const directionalLight = new THREE.DirectionalLight('#FFF', 0.6)
 					directionalLight.position.set(0, 10, 0)
-					this.stageGroup.add(directionalLight)
+					this.scene.add(directionalLight)
 				}
 
-				// Called once per frame, before render to give the app a chance to update this.stageGroup (a THREE.Group)
-				updateStageGroup(frame, stageCoordinateSystem, stagePose){
+				// Called once per frame, before render to give the app a chance to update the this.scene
+				updateScene(frame){
 					// Uncomment the next line to spin the teapot
-					//this.stageGroup.children[0].rotation.y += 0.01
+					//this.scene.children[0].rotation.y += 0.01
 				}
 			}
 
diff --git a/examples/common.js b/examples/common.js
index fcb2772..2a69e6f 100644
--- a/examples/common.js
+++ b/examples/common.js
@@ -26,14 +26,12 @@ class XRExampleBase {
 
 		// Create a simple THREE test scene for the layer
 		this.scene = new THREE.Scene() // The scene will be rotated and oriented around the camera using the head pose
-		this.stageGroup = new THREE.Group() // The group that stays on the "stage", which is at foot level relative to the head
-		this.scene.add(this.stageGroup)
 
 		this.camera = new THREE.PerspectiveCamera(70, 1024, 1024, 0.1, 1000) // These values will be overwritten by the projection matrix from ARKit or ARCore
 		this.renderer = null // Set in this.handleNewSession
 
-		// Give extending classes the opportunity to initially populate the stage group
-		this.initializeStageGroup(this.stageGroup)
+		// Give extending classes the opportunity to initially populate the scene
+		this.initializeScene()
 
 		if(typeof navigator.XR === 'undefined'){
 			this.showMessage('No WebXR API found, usually because the WebXR polyfill has not loaded')
@@ -154,46 +152,27 @@ class XRExampleBase {
 	handleLayerBlur(ev){}
 
 	/*
-	Extending classes should override this to set up the stageGroup during class construction
+	Extending classes should override this to set up the scene during class construction
 	*/
-	initializeStageGroup(){}
+	initializeScene(){}
 
 	/*
 	Extending classes that need to update the layer during each frame should override this method
 	*/
-	updateStageGroup(frame, stageCoordinateSystem, stagePose){}
+	updateScene(frame){}
 
 	handleFrame(frame){
 		const nextFrameRequest = this.session.requestFrame(frame => { this.handleFrame(frame) })
-		let stageCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.STAGE)
-		if(stageCoordinateSystem === null){
-			this.showMessage('Could not get a usable stage coordinate system')
-			this.session.cancelFrame(nextFrameRequest)
-			this.session.endSession()
-			// Production apps could render a 'waiting' message and keep checking for an acceptable coordinate system
-			return
-		}
-
-		// Get the two poses we care about: the foot level stage and head pose which is updated by ARKit, ARCore, or orientation events
-		let stagePose = frame.getViewPose(stageCoordinateSystem)
 		let headPose = frame.getViewPose(frame.getCoordinateSystem(XRCoordinateSystem.HEAD_MODEL))
 
-		// Let the extending class update the stageGroup before each render
-		this.updateStageGroup(frame, stageCoordinateSystem, stagePose)
-
-		// Update the stage group relative to the current head pose
-		this.stageGroup.matrixAutoUpdate = false
-		this.stageGroup.matrix.fromArray(stagePose.poseModelMatrix)
-		this.stageGroup.updateMatrixWorld(true)
+		// Let the extending class update the scene before each render
+		this.updateScene(frame)
 
 		// Prep THREE.js for the render of each XRView
-		//this.renderer.resetGLState()
-		this.scene.matrixAutoUpdate = false
 		this.renderer.autoClear = false
 		this.renderer.setSize(this.session.baseLayer.framebufferWidth, this.session.baseLayer.framebufferHeight, false)
 		this.renderer.clear()
-
-		//this.session.baseLayer.context.bindFramebuffer(this.session.baseLayer.context.FRAMEBUFFER, this.session.baseLayer.framebuffer)
+		this.scene.matrixAutoUpdate = false
 
 		// Render each view into this.session.baseLayer.context
 		for(const view of frame.views){
diff --git a/examples/hit_test/index.html b/examples/hit_test/index.html
index 067790d..8b7b860 100644
--- a/examples/hit_test/index.html
+++ b/examples/hit_test/index.html
@@ -47,7 +47,7 @@
 			class HitTestExample extends XRExampleBase {
 				constructor(domElement){
 					super(domElement, false)
-					this._tapEventData = null // Will be filled in on touch start and used in updateStageGroup
+					this._tapEventData = null // Will be filled in on touch start and used in updateScene
 
 					this.anchoredNodes = [] // { XRAnchorOffset, Three.js Object3D }
 
@@ -63,33 +63,33 @@
 					this.el.addEventListener('touchstart', this._onTouchStart.bind(this), false)
 				}
 
-				// Called during construction to allow the app to populate this.stageGroup (a THREE.Group)
-				initializeStageGroup(){
-					// Add a box at the stage origin to show where the stage group is located
+				// Called during construction to allow the app to populate this.scene
+				initializeScene(){
+					// Add a box at the scene origin
 					let box = new THREE.Mesh(
 						new THREE.BoxBufferGeometry(0.1, 0.1, 0.1),
 						new THREE.MeshPhongMaterial({ color: '#DDFFDD' })
 					)
 					box.position.set(0, 0, 0)
-					this.stageGroup.add(box)
+					this.scene.add(box)
 
-					// Add a box one meter in front of stage origin to show the direction of the Z axis
+					// Add a box one meter in front of scene origin to show the direction of the Z axis
 					box = new THREE.Mesh(
 						new THREE.BoxBufferGeometry(0.1, 0.1, 0.1),
 						new THREE.MeshPhongMaterial({ color: '#FF0000' })
 					)
 					box.position.set(0, 0, -1)
-					this.stageGroup.add(box)
+					this.scene.add(box)
 
 					// Add a few lights
-					this.stageGroup.add(new THREE.AmbientLight('#FFF', 0.2))
+					this.scene.add(new THREE.AmbientLight('#FFF', 0.2))
 					let directionalLight = new THREE.DirectionalLight('#FFF', 0.6)
 					directionalLight.position.set(0, 10, 0)
-					this.stageGroup.add(directionalLight)
+					this.scene.add(directionalLight)
 				}
 
-				// Called once per frame, before render, to give the app a chance to update this.stageGroup (a THREE.Group)
-				updateStageGroup(frame, stageCoordinateSystem, stagePose){
+				// Called once per frame, before render, to give the app a chance to update this.scene
+				updateScene(frame){
 					// If we have tap data, attempt a hit test for a surface
 					if(this._tapEventData !== null){
 						const x = this._tapEventData[0]
@@ -116,13 +116,14 @@
 
 								// Add a block to the scene to indicate the position of the XRAnchorOffset
 								// Its position will be updated below along with the other anchored nodes
-								this.stageGroup.add(anchorInfo.node)
+								this.scene.add(anchorInfo.node)
 							}
 						}).catch(err => {
 							console.error('Error in hit test', err)
 						})
 					}
 
+					const trackerCoordinateSystem = frame.getCoordinateSystem(XRCoordinateSystem.TRACKER)
 					// Update anchored node positions in the scene graph using updated anchor positions
 					for(let anchoredNode of this.anchoredNodes){
 						const anchor = frame.getAnchor(anchoredNode.anchorOffset.anchorUID)
@@ -131,17 +132,17 @@
 						} else {
 							anchoredNode.node.matrixAutoUpdate = false
 							let offsetCoordinates = anchoredNode.anchorOffset.getTransformedCoordinates(anchor)
-							if(offsetCoordinates.coordinateSystem.type === XRCoordinateSystem.STAGE){
+							if(offsetCoordinates.coordinateSystem.type === XRCoordinateSystem.TRACKER){
 								anchoredNode.node.matrix.fromArray(offsetCoordinates.poseMatrix)
 							} else {
-								anchoredNode.node.matrix.fromArray(offsetCoordinates.getTransformedCoordinates(stageCoordinateSystem).poseMatrix)
+								anchoredNode.node.matrix.fromArray(offsetCoordinates.getTransformedCoordinates(trackerCoordinateSystem).poseMatrix)
 							}
 							anchoredNode.node.updateMatrixWorld(true)
 						}
 					}
 				}
 
-				// Save screen taps as normalized coordinates for use in this.updateStageGroup
+				// Save screen taps as normalized coordinates for use in this.updateScene
 				_onTouchStart(ev){
 					if (!ev.touches || ev.touches.length === 0) {
 						console.error('No touches on touch event', ev)
diff --git a/examples/vr_simplest/index.html b/examples/vr_simplest/index.html
index 060110a..aa52782 100644
--- a/examples/vr_simplest/index.html
+++ b/examples/vr_simplest/index.html
@@ -50,7 +50,7 @@
 				}
 
 				// Called during construction
-				initializeStageGroup(){
+				initializeScene(){
 					// Add a teapot at about eye level
 					var geometry = new THREE.TeapotBufferGeometry(0.1)
 					let materialColor = new THREE.Color()
@@ -61,26 +61,26 @@
 					})
 					let mesh = new THREE.Mesh(geometry, material)
 					mesh.position.set(0, 1.6, -1)
-					this.stageGroup.add(mesh)
+					this.scene.add(mesh)
 
-					// Add a box at the stage origin
+					// Add a box at the scene origin
 					let box = new THREE.Mesh(
 						new THREE.BoxBufferGeometry(0.1, 0.1, 0.1),
 						new THREE.MeshPhongMaterial({ color: '#DDFFDD' })
 					)
 					box.position.set(0, 0, 0)
-					this.stageGroup.add(box)
+					this.scene.add(box)
 
-					this.stageGroup.add(new THREE.AmbientLight('#FFF', 0.2))
+					this.scene.add(new THREE.AmbientLight('#FFF', 0.2))
 					let directionalLight = new THREE.DirectionalLight('#FFF', 0.6)
 					directionalLight.position.set(0, 10, 0)
-					this.stageGroup.add(directionalLight)
+					this.scene.add(directionalLight)
 				}
 
 				// Called once per frame
-				updateStageGroup(frame, stageCoordinateSystem, stagePose){
+				updateScene(frame){
 					// Uncomment the next line to spin the box
-					// this.stageGroup.children[0].rotation.y += 0.01
+					// this.scene.children[0].rotation.y += 0.01
 				}
 			}
 
diff --git a/polyfill/XRCoordinateSystem.js b/polyfill/XRCoordinateSystem.js
index fa0b6e5..d115028 100644
--- a/polyfill/XRCoordinateSystem.js
+++ b/polyfill/XRCoordinateSystem.js
@@ -7,7 +7,7 @@ The XRCoordinateSystem is a string from XRCoordinateSystem.TYPES:
 
 - XRCoordinateSystem.HEAD_MODEL: origin is aligned with the pose of the head, as sensed by HMD or handset trackers
 - XRCoordinateSystem.EYE_LEVEL: origin is at a fixed distance above the ground
-- XRCoordinateSystem.STAGE: origin is at ground level
+- XRCoordinateSystem.TRACKER: The origin of this coordinate system is at floor level at or below the origin of the HMD or handset provided tracking system
 - XRCoordinateSystem.GEOSPATIAL: origin is at the East, Up, South plane tangent to the planet at the latitude, longitude, and altitude represented by the `XRCoordinateSystem.cartographicCoordinates`.
 
 */
@@ -28,8 +28,8 @@ export default class XRCoordinateSystem {
 				return this._display._headPose.poseModelMatrix
 			case XRCoordinateSystem.EYE_LEVEL:
 				return this._display._eyeLevelPose.poseModelMatrix
-			case XRCoordinateSystem.STAGE:
-				return this._display._stagePose.poseModelMatrix
+			case XRCoordinateSystem.TRACKER:
+				return this._display._trackerPoseModelMatrix
 			case XRCoordinateSystem.GEOSPATIAL:
 				throw 'This polyfill does not yet handle geospatial coordinate systems'
 			default:
@@ -60,14 +60,14 @@ export default class XRCoordinateSystem {
 	}
 }
 
-XRCoordinateSystem.HEAD_MODEL = "headModel"
-XRCoordinateSystem.EYE_LEVEL = "eyeLevel"
-XRCoordinateSystem.STAGE = "stage"
-XRCoordinateSystem.GEOSPATIAL = "geospatial"
+XRCoordinateSystem.HEAD_MODEL = 'headModel'
+XRCoordinateSystem.EYE_LEVEL = 'eyeLevel'
+XRCoordinateSystem.TRACKER = 'tracker'
+XRCoordinateSystem.GEOSPATIAL = 'geospatial'
 
 XRCoordinateSystem.TYPES = [
 	XRCoordinateSystem.HEAD_MODEL,
 	XRCoordinateSystem.EYE_LEVEL,
-	XRCoordinateSystem.STAGE,
+	XRCoordinateSystem.TRACKER,
 	XRCoordinateSystem.GEOSPATIAL
 ]
\ No newline at end of file
diff --git a/polyfill/XRDisplay.js b/polyfill/XRDisplay.js
index 1edd330..bc9cda1 100644
--- a/polyfill/XRDisplay.js
+++ b/polyfill/XRDisplay.js
@@ -18,11 +18,16 @@ export default class XRDisplay extends EventHandlerBase {
 
 		this._headModelCoordinateSystem = new XRCoordinateSystem(this, XRCoordinateSystem.HEAD_MODEL)
 		this._eyeLevelCoordinateSystem = new XRCoordinateSystem(this, XRCoordinateSystem.EYE_LEVEL)
-		this._stageCoordinateSystem = new XRCoordinateSystem(this, XRCoordinateSystem.STAGE)
+		this._trackerCoordinateSystem = new XRCoordinateSystem(this, XRCoordinateSystem.TRACKER)
 
 		this._headPose = new XRViewPose([0, XRViewPose.SITTING_EYE_HEIGHT, 0])
 		this._eyeLevelPose = new XRViewPose([0, XRViewPose.SITTING_EYE_HEIGHT, 0])
-		this._stagePose = new XRViewPose([0, 0, 0])
+		this._trackerPoseModelMatrix = new Float32Array([
+			1, 0, 0, 0,
+			0, 1, 0, 0,
+			0, 0, 1, 0,
+			0, 0, 0, 1
+		])
 
 		var fov = 50/2;
 		this._fov = new XRFieldOfView(fov, fov, fov, fov)
diff --git a/polyfill/XRPresentationFrame.js b/polyfill/XRPresentationFrame.js
index 9d3dde5..2de7955 100644
--- a/polyfill/XRPresentationFrame.js
+++ b/polyfill/XRPresentationFrame.js
@@ -86,8 +86,6 @@ export default class XRPresentationFrame {
 				return this._session._display._headPose
 			case XRCoordinateSystem.EYE_LEVEL:
 				return this._session._display._eyeLevelPose
-			case XRCoordinateSystem.STAGE:
-				return this._session._display._stagePose
 			default:
 				return null
 		}
diff --git a/polyfill/XRSession.js b/polyfill/XRSession.js
index cc944ad..a59a5cf 100644
--- a/polyfill/XRSession.js
+++ b/polyfill/XRSession.js
@@ -75,8 +75,8 @@ export default class XRSession extends EventHandlerBase {
 					return this._display._headModelCoordinateSystem
 				case XRCoordinateSystem.EYE_LEVEL:
 					return this._display._eyeLevelCoordinateSystem
-				case XRCoordinateSystem.STAGE:
-					return this._display._stageCoordinateSystem
+				case XRCoordinateSystem.TRACKER:
+					return this._display._trackerCoordinateSystem
 				case XRCoordinateSystem.GEOSPATIAL:
 					// Not supported yet
 				default:
diff --git a/polyfill/XRStageBounds.js b/polyfill/XRStageBounds.js
index f6cea8d..39290ad 100644
--- a/polyfill/XRStageBounds.js
+++ b/polyfill/XRStageBounds.js
@@ -6,11 +6,11 @@ Other XR platforms sometimes refer to this concept as "room scale" or "standing
 export default class XRStageBounds {
 	get center(){
 		//readonly attribute XRCoordinates center;
-		throw 'Not implemented'
+		throw new Error('Not implemented')
 	}
 
 	get geometry(){
 		//readonly attribute FrozenArray<XRStageBoundsPoint>? geometry;
-		throw 'Not implemented'
+		throw new Error('Not implemented')
 	}
 }
\ No newline at end of file
diff --git a/polyfill/XRStageBoundsPoint.js b/polyfill/XRStageBoundsPoint.js
index 9d144a2..629b233 100644
--- a/polyfill/XRStageBoundsPoint.js
+++ b/polyfill/XRStageBoundsPoint.js
@@ -4,11 +4,11 @@ XRStageBoundPoints represent the offset in meters from the stage origin along th
 export default class XRStageBoundsPoint {
 	get x(){
 		//readonly attribute double x;
-		throw 'Not implemented'
+		throw new Error('Not implemented')
 	}
 
 	get y(){
 		//readonly attribute double z;
-		throw 'Not implemented'
+		throw new Error('Not implemented')
 	}
 }
\ No newline at end of file
diff --git a/polyfill/display/FlatDisplay.js b/polyfill/display/FlatDisplay.js
index da8590a..77edbf1 100644
--- a/polyfill/display/FlatDisplay.js
+++ b/polyfill/display/FlatDisplay.js
@@ -109,7 +109,6 @@ export default class FlatDisplay extends XRDisplay {
 		MatrixMath.mat4_fromRotationTranslation(this._deviceWorldMatrix, this._deviceOrientation.toArray(), this._devicePosition.toArray())
 		this._headPose._setPoseModelMatrix(this._deviceWorldMatrix)
 		this._eyeLevelPose._position = this._devicePosition.toArray()
-		this._stagePose._position = [0, 0, 0]
 	}
 
 	_updateFromDeviceOrientationTracker(){
@@ -120,7 +119,6 @@ export default class FlatDisplay extends XRDisplay {
 		MatrixMath.mat4_fromRotationTranslation(this._deviceWorldMatrix, this._deviceOrientation.toArray(), this._devicePosition.toArray())
 		this._headPose._setPoseModelMatrix(this._deviceWorldMatrix)
 		this._eyeLevelPose._position = this._devicePosition.toArray()
-		this._stagePose._position = [0, 0, 0]
 	}
 
 	_handleARKitUpdate(...params){
@@ -129,7 +127,6 @@ export default class FlatDisplay extends XRDisplay {
 			this._headPose._setPoseModelMatrix(cameraTransformMatrix)
 			this._headPose._poseModelMatrix[13] += XRViewPose.SITTING_EYE_HEIGHT
 			this._eyeLevelPose._position = this._headPose._position
-			this._stagePose._position = [0, 0, 0]
 		} else {
 			console.log('no camera transform', this._arKitWrapper.rawARData)
 		}
diff --git a/polyfill/display/HeadMountedDisplay.js b/polyfill/display/HeadMountedDisplay.js
index 3f61b1f..4089210 100644
--- a/polyfill/display/HeadMountedDisplay.js
+++ b/polyfill/display/HeadMountedDisplay.js
@@ -98,7 +98,6 @@ export default class HeadMountedDisplay extends XRDisplay {
 			}
 			this._headPose._setPoseModelMatrix(this._deviceWorldMatrix)
 			this._eyeLevelPose.position = this._devicePosition.toArray()
-			this._stagePose._position = [0, 0, 0]
 		}
 	}
 }
\ No newline at end of file
diff --git a/polyfill/reality/CameraReality.js b/polyfill/reality/CameraReality.js
index 571382e..a90a14e 100644
--- a/polyfill/reality/CameraReality.js
+++ b/polyfill/reality/CameraReality.js
@@ -150,13 +150,13 @@ export default class CameraReality extends Reality {
 			console.log('unknown anchor', anchor)
 			return
 		}
-		// This assumes that the anchor's coordinates are in the stage coordinate system
+		// This assumes that the anchor's coordinates are in the tracker coordinate system
 		anchor.coordinates.poseMatrix = anchorInfo.transform
 	}
 
 	_addAnchor(anchor, display){
-		// Convert coordinates to the stage coordinate system so that updating from ARKit transforms is simple
-		anchor.coordinates = anchor.coordinates.getTransformedCoordinates(display._stageCoordinateSystem)
+		// Convert coordinates to the tracker coordinate system so that updating from ARKit transforms is simple
+		anchor.coordinates = anchor.coordinates.getTransformedCoordinates(display._trackerCoordinateSystem)
 		if(this._arKitWrapper !== null){
 			this._arKitWrapper.addAnchor(anchor.uid, anchor.coordinates.poseMatrix).then(
 				detail => this._handleARKitAddObject(detail)
@@ -192,7 +192,7 @@ export default class CameraReality extends Reality {
 
 					let anchor = this._getAnchor(hit.uuid)
 					if(anchor === null){
-						let anchorCoordinates = new XRCoordinates(display, display._stageCoordinateSystem)
+						let anchorCoordinates = new XRCoordinates(display, display._trackerCoordinateSystem)
 						anchorCoordinates.poseMatrix = hit.anchor_transform
 						anchor = new XRAnchor(anchorCoordinates, hit.uuid)
 						this._anchors.set(anchor.uid, anchor)
@@ -220,7 +220,7 @@ export default class CameraReality extends Reality {
 				hits.sort((a, b) => a.distance - b.distance)
 				let anchor = this._getAnchor(hits[0].uuid)
 				if(anchor === null){
-					let coordinates = new XRCoordinates(display, display._stageCoordinateSystem)
+					let coordinates = new XRCoordinates(display, display._trackerCoordinateSystem)
 					coordinates.poseMatrix = hits[0].modelMatrix
 					coordinates._poseMatrix[13] += XRViewPose.SITTING_EYE_HEIGHT
 					anchor = new XRAnchor(coordinates)
diff --git a/tests/CoordinatesTest.js b/tests/CoordinatesTest.js
index 8d2c757..add15bc 100644
--- a/tests/CoordinatesTest.js
+++ b/tests/CoordinatesTest.js
@@ -9,29 +9,29 @@ import Quaternion from '../polyfill/fill/Quaternion.js'
 export default class CoordinatesTest extends Test {
 	testTransform(){
 		let display1 = new MockXRDisplay()
-		let stageCoordinateSystem = new XRCoordinateSystem(display1, XRCoordinateSystem.STAGE)
+		let trackerCoordinateSystem = new XRCoordinateSystem(display1, XRCoordinateSystem.TRACKER)
 		let headCoordinateSystem = new XRCoordinateSystem(display1, XRCoordinateSystem.HEAD_MODEL)
 		let eyeLevelCoordinateSystem = new XRCoordinateSystem(display1, XRCoordinateSystem.EYE_LEVEL)
 
 		let headCoordinates = new XRCoordinates(display1, headCoordinateSystem, [0, 0, -0.5])
-		let stageCoordinates = headCoordinates.getTransformedCoordinates(stageCoordinateSystem)
+		let trackerCoordinates = headCoordinates.getTransformedCoordinates(trackerCoordinateSystem)
 		this.assertFloatArraysEqual(
-			stageCoordinates.position, 
+			trackerCoordinates.position, 
 			[headCoordinates.position[0], XRViewPose.SITTING_EYE_HEIGHT + headCoordinates.position[1], headCoordinates.position[2]]
 		)
-		this.assertFloatArraysEqual(stageCoordinates.orientation, headCoordinates.orientation)
+		this.assertFloatArraysEqual(trackerCoordinates.orientation, headCoordinates.orientation)
 
 		// Rotate the head and test the transform
 		let quat1 = new Quaternion()
 		quat1.setFromEuler(0, -Math.PI, 0)
 		display1._headPose._orientation = quat1.toArray()
-		stageCoordinates = headCoordinates.getTransformedCoordinates(stageCoordinateSystem)
+		trackerCoordinates = headCoordinates.getTransformedCoordinates(trackerCoordinateSystem)
 		this.assertFloatArraysEqual(
-			stageCoordinates.position,
+			trackerCoordinates.position,
 			[headCoordinates.position[0], XRViewPose.SITTING_EYE_HEIGHT + headCoordinates.position[1], -1 * headCoordinates.position[2]]
 		)
 		quat1.inverse()
-		this.assertFloatArraysEqual(quat1.toArray(), stageCoordinates.orientation)
+		this.assertFloatArraysEqual(quat1.toArray(), trackerCoordinates.orientation)
 	}
 }