diff --git a/package.json b/package.json
index 4f59683..aed9b82 100644
--- a/package.json
+++ b/package.json
@@ -20,8 +20,8 @@
   "license": "MIT",
   "homepage": "https://github.com/maputnik/editor#readme",
   "dependencies": {
-    "@mapbox/mapbox-gl-style-spec": "^9.0.0",
     "@mapbox/mapbox-gl-rtl-text": "^0.1.0",
+    "@mapbox/mapbox-gl-style-spec": "^9.0.1",
     "classnames": "^2.2.5",
     "codemirror": "^5.18.2",
     "color": "^1.0.3",
@@ -32,7 +32,7 @@
     "lodash.clonedeep": "^4.5.0",
     "lodash.isequal": "^4.4.0",
     "lodash.throttle": "^4.1.1",
-    "mapbox-gl": "^0.34.0",
+    "mapbox-gl": "^0.40.1",
     "mapbox-gl-inspect": "^1.2.3",
     "maputnik-design": "github:maputnik/design",
     "mousetrap": "^1.6.0",
diff --git a/src/components/fields/FunctionSpecField.jsx b/src/components/fields/FunctionSpecField.jsx
new file mode 100644
index 0000000..2b7383b
--- /dev/null
+++ b/src/components/fields/FunctionSpecField.jsx
@@ -0,0 +1,352 @@
+import React from 'react'
+import Color from 'color'
+
+import Button from '../Button'
+import SpecField from './SpecField'
+import NumberInput from '../inputs/NumberInput'
+import StringInput from '../inputs/StringInput'
+import SelectInput from '../inputs/SelectInput'
+import DocLabel from './DocLabel'
+import InputBlock from '../inputs/InputBlock'
+
+import AddIcon from 'react-icons/lib/md/add-circle-outline'
+import DeleteIcon from 'react-icons/lib/md/delete'
+import FunctionIcon from 'react-icons/lib/md/functions'
+import MdInsertChart from 'react-icons/lib/md/insert-chart'
+
+import capitalize from 'lodash.capitalize'
+
+function isZoomField(value) {
+  return typeof value === 'object' && value.stops && typeof value.property === 'undefined'
+}
+
+function isDataField(value) {
+  return typeof value === 'object' && value.stops && typeof value.property !== 'undefined'
+}
+
+/** Supports displaying spec field for zoom function objects
+ * https://www.mapbox.com/mapbox-gl-style-spec/#types-function-zoom-property
+ */
+export default class FunctionSpecProperty  extends React.Component {
+  static propTypes = {
+      onChange: React.PropTypes.func.isRequired,
+      fieldName: React.PropTypes.string.isRequired,
+      fieldSpec: React.PropTypes.object.isRequired,
+
+      value: React.PropTypes.oneOfType([
+      React.PropTypes.object,
+      React.PropTypes.string,
+      React.PropTypes.number,
+      React.PropTypes.bool,
+      React.PropTypes.array
+    ]),
+  }
+
+  addStop() {
+    const stops = this.props.value.stops.slice(0)
+    const lastStop = stops[stops.length - 1]
+    if (typeof lastStop[0] === "object") {
+      stops.push([
+        {zoom: lastStop[0].zoom + 1, value: lastStop[0].value},
+        lastStop[1]
+      ])
+    }
+    else {
+      stops.push([lastStop[0] + 1, lastStop[1]])
+    }
+
+    const changedValue = {
+      ...this.props.value,
+      stops: stops,
+    }
+
+    this.props.onChange(this.props.fieldName, changedValue)
+  }
+
+  deleteStop(stopIdx) {
+    const stops = this.props.value.stops.slice(0)
+    stops.splice(stopIdx, 1)
+
+    let changedValue = {
+      ...this.props.value,
+      stops: stops,
+    }
+
+    if(stops.length === 1) {
+      changedValue = stops[0][1]
+    }
+
+    this.props.onChange(this.props.fieldName, changedValue)
+  }
+
+  makeZoomFunction() {
+    const zoomFunc = {
+      stops: [
+        [6, this.props.value],
+        [10, this.props.value]
+      ]
+    }
+    this.props.onChange(this.props.fieldName, zoomFunc)
+  }
+
+  getDataFunctionTypes(functionType) {
+    if (functionType === "interpolated") {
+      return ["categorical", "interval", "exponential"]
+    }
+    else {
+      return ["categorical", "interval"]
+    }
+  }
+
+  makeDataFunction() {
+    const dataFunc = {
+      property: "",
+      type: "categorical",
+      stops: [
+        [{zoom: 6, value: 0}, this.props.value],
+        [{zoom: 10, value: 0}, this.props.value]
+      ]
+    }
+    this.props.onChange(this.props.fieldName, dataFunc)
+  }
+
+  changeStop(changeIdx, stopData, value) {
+    const stops = this.props.value.stops.slice(0)
+    stops[changeIdx] = [stopData, value]
+    const changedValue = {
+      ...this.props.value,
+      stops: stops,
+    }
+    this.props.onChange(this.props.fieldName, changedValue)
+  }
+
+  changeDataProperty(propName, propVal) {
+    if (propVal) {
+      this.props.value[propName] = propVal
+    }
+    else {
+      delete this.props.value[propName]
+    }
+    this.props.onChange(this.props.fieldName, this.props.value)
+  }
+
+  renderDataProperty() {
+    const dataFields = this.props.value.stops.map((stop, idx) => {
+      const zoomLevel = stop[0].zoom
+      const dataLevel = stop[0].value
+      const value = stop[1]
+      const deleteStopBtn = <DeleteStopButton onClick={this.deleteStop.bind(this, idx)} />
+
+      const dataProps = {
+        label: "Data value",
+        value: dataLevel,
+        onChange: newData => this.changeStop(idx, { zoom: zoomLevel, value: newData }, value)
+      }
+      const dataInput = this.props.value.type === "categorical" ? <StringInput {...dataProps} /> : <NumberInput {...dataProps} />
+
+      return <InputBlock key={idx} action={deleteStopBtn}>
+        <div className="maputnik-data-spec-property-stop-edit">
+          <NumberInput
+            value={zoomLevel}
+            onChange={newZoom => this.changeStop(idx, {zoom: newZoom, value: dataLevel}, value)}
+            min={0}
+            max={22}
+          />
+        </div>
+        <div className="maputnik-data-spec-property-stop-data">
+          {dataInput}
+        </div>
+        <div className="maputnik-data-spec-property-stop-value">
+          <SpecField
+            fieldName={this.props.fieldName}
+            fieldSpec={this.props.fieldSpec}
+            value={value}
+            onChange={(_, newValue) => this.changeStop(idx, {zoom: zoomLevel, value: dataLevel}, newValue)}
+          />
+        </div>
+      </InputBlock>
+    })
+
+    return <div className="maputnik-data-spec-block">
+    <div className="maputnik-data-spec-property">
+      <InputBlock
+        doc={this.props.fieldSpec.doc}
+        label={labelFromFieldName(this.props.fieldName)}
+      >
+        <div className="maputnik-data-spec-property-group">
+          <DocLabel
+            label="Property"
+            doc={"Input a data property to base styles off of."}
+          />
+          <div className="maputnik-data-spec-property-input">
+            <StringInput
+              value={this.props.value.property}
+              onChange={propVal => this.changeDataProperty("property", propVal)}
+            />
+          </div>
+        </div>
+        <div className="maputnik-data-spec-property-group">
+          <DocLabel
+            label="Type"
+            doc={"Select a type of data scale (default is 'categorical')."}
+          />
+          <div className="maputnik-data-spec-property-input">
+            <SelectInput
+              value={this.props.value.type}
+              onChange={propVal => this.changeDataProperty("type", propVal)}
+              options={this.getDataFunctionTypes(this.props.fieldSpec.function)}
+            />
+          </div>
+        </div>
+        <div className="maputnik-data-spec-property-group">
+          <DocLabel
+            label="Default"
+            doc={"Input a default value for data if not covered by the scales."}
+          />
+          <div className="maputnik-data-spec-property-input">
+            <SpecField
+              fieldName={this.props.fieldName}
+              fieldSpec={this.props.fieldSpec}
+              value={this.props.value.default}
+              onChange={(_, propVal) => this.changeDataProperty("default", propVal)}
+            />
+          </div>
+        </div>
+      </InputBlock>
+    </div>
+      {dataFields}
+      <Button
+        className="maputnik-add-stop"
+        onClick={this.addStop.bind(this)}
+      >
+        Add stop
+      </Button>
+    </div>
+  }
+
+  renderZoomProperty() {
+    const zoomFields = this.props.value.stops.map((stop, idx) => {
+      const zoomLevel = stop[0]
+      const value = stop[1]
+      const deleteStopBtn= <DeleteStopButton onClick={this.deleteStop.bind(this, idx)} />
+
+      return <InputBlock
+        key={zoomLevel}
+        doc={this.props.fieldSpec.doc}
+        label={labelFromFieldName(this.props.fieldName)}
+        action={deleteStopBtn}
+      >
+        <div>
+          <div className="maputnik-zoom-spec-property-stop-edit">
+            <NumberInput
+              value={zoomLevel}
+              onChange={changedStop => this.changeStop(idx, changedStop, value)}
+              min={0}
+              max={22}
+            />
+          </div>
+          <div className="maputnik-zoom-spec-property-stop-value">
+            <SpecField
+              fieldName={this.props.fieldName}
+              fieldSpec={this.props.fieldSpec}
+              value={value}
+              onChange={(_, newValue) => this.changeStop(idx, zoomLevel, newValue)}
+            />
+          </div>
+        </div>
+      </InputBlock>
+    })
+
+    return <div className="maputnik-zoom-spec-property">
+      {zoomFields}
+      <Button
+        className="maputnik-add-stop"
+        onClick={this.addStop.bind(this)}
+      >
+        Add stop
+      </Button>
+    </div>
+  }
+
+  renderProperty() {
+    const functionBtn = <MakeFunctionButtons
+      fieldSpec={this.props.fieldSpec}
+      onZoomClick={this.makeZoomFunction.bind(this)}
+      onDataClick={this.makeDataFunction.bind(this)} 
+    />
+    return <InputBlock
+      doc={this.props.fieldSpec.doc}
+      label={labelFromFieldName(this.props.fieldName)}
+      action={functionBtn}
+    >
+      <SpecField {...this.props} />
+    </InputBlock>
+  }
+
+  render() {
+    const propClass = this.props.fieldSpec.default === this.props.value ? "maputnik-default-property" : "maputnik-modified-property"
+    let specField
+    if (isZoomField(this.props.value)) {
+      specField = this.renderZoomProperty()
+    }
+    else if (isDataField(this.props.value)) {
+      specField = this.renderDataProperty()
+    }
+    else {
+      specField = this.renderProperty()
+    }
+    return <div className={propClass}>
+      {specField}
+    </div>
+  }
+}
+
+function MakeFunctionButtons(props) {
+  let makeZoomButton, makeDataButton
+  if (props.fieldSpec['zoom-function']) {
+    makeZoomButton = <Button
+      className="maputnik-make-zoom-function"
+      onClick={props.onZoomClick}
+    >
+      <DocLabel
+        label={<FunctionIcon />}
+        cursorTargetStyle={{ cursor: 'pointer' }}
+        doc={"Turn property into a zoom function to enable a map feature to change with map's zoom level."}
+      />
+    </Button>
+
+    if (props.fieldSpec['property-function'] && ['piecewise-constant', 'interpolated'].indexOf(props.fieldSpec['function']) !== -1) {
+      makeDataButton = <Button
+        className="maputnik-make-data-function"
+        onClick={props.onDataClick}
+      >
+        <DocLabel
+          label={<MdInsertChart />}
+          cursorTargetStyle={{ cursor: 'pointer' }}
+          doc={"Turn property into a data function to enable a map feature to change according to data properties and the map's zoom level."}
+        />
+      </Button>
+    }
+    return <div>{makeDataButton}{makeZoomButton}</div>
+  }
+  else {
+    return null
+  }
+}
+
+function DeleteStopButton(props) {
+  return <Button
+    className="maputnik-delete-stop"
+    onClick={props.onClick}
+  >
+    <DocLabel
+      label={<DeleteIcon />}
+      doc={"Remove zoom level stop."}
+    />
+  </Button>
+}
+
+function labelFromFieldName(fieldName) {
+  let label = fieldName.split('-').slice(1).join(' ')
+  return capitalize(label)
+}
diff --git a/src/components/fields/PropertyGroup.jsx b/src/components/fields/PropertyGroup.jsx
index 8de8b34..fc17892 100644
--- a/src/components/fields/PropertyGroup.jsx
+++ b/src/components/fields/PropertyGroup.jsx
@@ -1,6 +1,6 @@
 import React from 'react'
 
-import ZoomSpecField from './ZoomSpecField'
+import FunctionSpecField from './FunctionSpecField'
 const iconProperties = ['background-pattern', 'fill-pattern', 'line-pattern', 'fill-extrusion-pattern', 'icon-image']
 
 /** Extract field spec by {@fieldName} from the {@layerType} in the
@@ -54,7 +54,7 @@ export default class PropertyGroup extends React.Component {
       const layout = this.props.layer.layout || {}
       const fieldValue = fieldName in paint ? paint[fieldName] : layout[fieldName]
 
-      return <ZoomSpecField
+      return <FunctionSpecField
         onChange={this.onPropertyChange.bind(this)}
         key={fieldName}
         fieldName={fieldName}
diff --git a/src/components/fields/ZoomSpecField.jsx b/src/components/fields/ZoomSpecField.jsx
deleted file mode 100644
index 9f8e755..0000000
--- a/src/components/fields/ZoomSpecField.jsx
+++ /dev/null
@@ -1,181 +0,0 @@
-import React from 'react'
-import Color from 'color'
-
-import Button from '../Button'
-import SpecField from './SpecField'
-import NumberInput from '../inputs/NumberInput'
-import DocLabel from './DocLabel'
-import InputBlock from '../inputs/InputBlock'
-
-import AddIcon from 'react-icons/lib/md/add-circle-outline'
-import DeleteIcon from 'react-icons/lib/md/delete'
-import FunctionIcon from 'react-icons/lib/md/functions'
-
-import capitalize from 'lodash.capitalize'
-
-function isZoomField(value) {
-  return typeof value === 'object' && value.stops
-}
-
-/** Supports displaying spec field for zoom function objects
- * https://www.mapbox.com/mapbox-gl-style-spec/#types-function-zoom-property
- */
-export default class ZoomSpecProperty  extends React.Component {
-  static propTypes = {
-      onChange: React.PropTypes.func.isRequired,
-      fieldName: React.PropTypes.string.isRequired,
-      fieldSpec: React.PropTypes.object.isRequired,
-
-      value: React.PropTypes.oneOfType([
-      React.PropTypes.object,
-      React.PropTypes.string,
-      React.PropTypes.number,
-      React.PropTypes.bool,
-      React.PropTypes.array
-    ]),
-  }
-
-  addStop() {
-    const stops = this.props.value.stops.slice(0)
-    const lastStop = stops[stops.length - 1]
-    stops.push([lastStop[0] + 1, lastStop[1]])
-
-    const changedValue = {
-      ...this.props.value,
-      stops: stops,
-    }
-
-    this.props.onChange(this.props.fieldName, changedValue)
-  }
-
-  deleteStop(stopIdx) {
-    const stops = this.props.value.stops.slice(0)
-    stops.splice(stopIdx, 1)
-
-    let changedValue = {
-      ...this.props.value,
-      stops: stops,
-    }
-
-    if(stops.length === 1) {
-      changedValue = stops[0][1]
-    }
-
-    this.props.onChange(this.props.fieldName, changedValue)
-  }
-
-  makeZoomFunction() {
-    const zoomFunc = {
-      stops: [
-        [6, this.props.value],
-        [10, this.props.value]
-      ]
-    }
-    this.props.onChange(this.props.fieldName, zoomFunc)
-  }
-
-  changeStop(changeIdx, zoomLevel, value) {
-    const stops = this.props.value.stops.slice(0)
-    stops[changeIdx] = [zoomLevel, value]
-    const changedValue = {
-      ...this.props.value,
-      stops: stops,
-    }
-    this.props.onChange(this.props.fieldName, changedValue)
-  }
-
-  renderZoomProperty() {
-    const zoomFields = this.props.value.stops.map((stop, idx) => {
-      const zoomLevel = stop[0]
-      const value = stop[1]
-      const deleteStopBtn= <DeleteStopButton onClick={this.deleteStop.bind(this, idx)} />
-
-      return <InputBlock
-        key={zoomLevel}
-        doc={this.props.fieldSpec.doc}
-        label={labelFromFieldName(this.props.fieldName)}
-        action={deleteStopBtn}
-      >
-        <div>
-          <div className="maputnik-zoom-spec-property-stop-edit">
-            <NumberInput
-              value={zoomLevel}
-              onChange={changedStop => this.changeStop(idx, changedStop, value)}
-              min={0}
-              max={22}
-            />
-          </div>
-          <div className="maputnik-zoom-spec-property-stop-value">
-            <SpecField
-              fieldName={this.props.fieldName}
-              fieldSpec={this.props.fieldSpec}
-              value={value}
-              onChange={(_, newValue) => this.changeStop(idx, zoomLevel, newValue)}
-            />
-          </div>
-        </div>
-      </InputBlock>
-    })
-
-    return <div className="maputnik-zoom-spec-property">
-      {zoomFields}
-      <Button
-        className="maputnik-add-stop"
-        onClick={this.addStop.bind(this)}
-      >
-        Add stop
-      </Button>
-    </div>
-  }
-
-  renderProperty() {
-    let zoomBtn = null
-    if(this.props.fieldSpec['zoom-function']) {
-      zoomBtn = <MakeZoomFunctionButton onClick={this.makeZoomFunction.bind(this)} />
-    }
-    return <InputBlock
-      doc={this.props.fieldSpec.doc}
-      label={labelFromFieldName(this.props.fieldName)}
-      action={zoomBtn}
-    >
-      <SpecField {...this.props} />
-    </InputBlock>
-  }
-
-  render() {
-    const propClass = this.props.fieldSpec.default === this.props.value ? "maputnik-default-property" : "maputnik-modified-property"
-    return <div className={propClass}>
-      {isZoomField(this.props.value) ? this.renderZoomProperty() : this.renderProperty()}
-    </div>
-  }
-}
-
-function MakeZoomFunctionButton(props) {
-  return <Button
-    className="maputnik-make-zoom-function"
-    onClick={props.onClick}
-  >
-    <DocLabel
-      label={<FunctionIcon />}
-      cursorTargetStyle={{ cursor: 'pointer' }}
-      doc={"Turn property into a zoom function to enable a map feature to change with map's zoom level."}
-    />
-  </Button>
-}
-
-function DeleteStopButton(props) {
-  return <Button
-    className="maputnik-delete-stop"
-    onClick={props.onClick}
-  >
-    <DocLabel
-      label={<DeleteIcon />}
-      doc={"Remove zoom level stop."}
-    />
-  </Button>
-}
-
-function labelFromFieldName(fieldName) {
-  let label = fieldName.split('-').slice(1).join(' ')
-  return capitalize(label)
-}
diff --git a/src/styles/_components.scss b/src/styles/_components.scss
index b4032a5..12415fa 100644
--- a/src/styles/_components.scss
+++ b/src/styles/_components.scss
@@ -40,6 +40,7 @@
 
 .maputnik-doc-target:hover .maputnik-doc-popup {
   display: block;
+  text-align: left;
 }
 
 // BUTTON
@@ -104,13 +105,17 @@
 .maputnik-action-block {
   .maputnik-input-block-label {
     display: inline-block;
-    width: 43%;
+    width: 35%;
   }
 
   .maputnik-input-block-action {
     vertical-align: top;
     display: inline-block;
-    width: 7%;
+    width: 15%;
+  }
+
+  .maputnik-input-block-action > div {
+    text-align: right;
   }
 }
 
diff --git a/src/styles/_zoomproperty.scss b/src/styles/_zoomproperty.scss
index 2298496..d6510c9 100644
--- a/src/styles/_zoomproperty.scss
+++ b/src/styles/_zoomproperty.scss
@@ -67,3 +67,68 @@
 .maputnik-zoom-spec-property .maputnik-input-block:not(:first-child) .maputnik-input-block-label {
   visibility: hidden;
 }
+
+// DATA FUNC
+.maputnik-make-data-function {
+  background-color: transparent;
+  display: inline-block;
+  padding-bottom: 0;
+  padding-top: 0;
+  vertical-align: middle;
+
+  @extend .maputnik-icon-button;
+}
+
+// DATA PROPERTY
+.maputnik-data-spec-block {
+  overflow: auto;
+}
+
+.maputnik-data-spec-property {
+  .maputnik-input-block-label {
+    width: 30%;
+  }
+
+  .maputnik-input-block-content {
+    width: 70%;
+  }
+
+  .maputnik-data-spec-property-group {
+    margin-bottom: 3%;
+
+    .maputnik-doc-wrapper {
+      width: 25%;
+      color: $color-lowgray;
+    }
+
+    .maputnik-doc-wrapper:hover {
+      color: inherit;
+    }
+
+    .maputnik-data-spec-property-input {
+      width: 75%;
+      display: inline-block;
+
+      .maputnik-string {
+        margin-bottom: 3%;
+      }
+    }
+  }
+}
+
+.maputnik-data-spec-block {
+  .maputnik-data-spec-property-stop-edit,
+  .maputnik-data-spec-property-stop-data {
+    display: inline-block;
+    margin-bottom: 3%;
+  }
+
+  .maputnik-data-spec-property-stop-edit {
+    width: 18%;
+    margin-right: 3%;
+  }
+
+  .maputnik-data-spec-property-stop-data {
+    width: 78%;
+  }
+}