diff --git a/src/ui/CalldataPanel.js b/src/ui/CalldataPanel.js
index f5e6aa550f..e2fef57b74 100644
--- a/src/ui/CalldataPanel.js
+++ b/src/ui/CalldataPanel.js
@@ -5,7 +5,7 @@ var yo = require('yo-yo')
 function CalldataPanel (_parent, _traceManager) {
   this.parent = _parent
   this.traceManager = _traceManager
-  this.basicPanel = new DropdownPanel('Call Data')
+  this.basicPanel = new DropdownPanel('Call Data', {json: true})
   this.init()
 }
 
diff --git a/src/ui/CallstackPanel.js b/src/ui/CallstackPanel.js
index 6ceeca026c..a9ecdbac5e 100644
--- a/src/ui/CallstackPanel.js
+++ b/src/ui/CallstackPanel.js
@@ -5,7 +5,7 @@ var yo = require('yo-yo')
 function CallstackPanel (_parent, _traceManager) {
   this.parent = _parent
   this.traceManager = _traceManager
-  this.basicPanel = new DropdownPanel('Call Stack')
+  this.basicPanel = new DropdownPanel('Call Stack', {json: true})
   this.init()
 }
 
diff --git a/src/ui/CodeListView.js b/src/ui/CodeListView.js
index d355dbb751..3dc8fe0022 100644
--- a/src/ui/CodeListView.js
+++ b/src/ui/CodeListView.js
@@ -11,7 +11,7 @@ function CodeListView (_parent, _codeManager) {
   this.address
   this.codeView
   this.itemSelected
-  this.basicPanel = new DropdownPanel('Instructions', true)
+  this.basicPanel = new DropdownPanel('Instructions', {json: false})
   this.init()
 }
 
@@ -51,8 +51,7 @@ CodeListView.prototype.changed = function (code, address, index) {
     this.code = code
     this.address = address
     this.codeView = this.renderAssemblyItems()
-    this.basicPanel.data = this.codeView
-    this.basicPanel.update()
+    this.basicPanel.setContent(this.codeView)
   }
   this.indexChanged(index)
 }
diff --git a/src/ui/DropdownPanel.js b/src/ui/DropdownPanel.js
index 1caf7ea2dc..8f36e1071d 100644
--- a/src/ui/DropdownPanel.js
+++ b/src/ui/DropdownPanel.js
@@ -3,49 +3,40 @@ var yo = require('yo-yo')
 var ui = require('../helpers/ui')
 var styleDropdown = require('./styles/dropdownPanel')
 var basicStyles = require('./styles/basicStyles')
+var TreeView = require('./TreeView')
 
-function DropdownPanel (_name, _raw) {
-  this.data
+function DropdownPanel (_name, _opts) {
+  if (!_opts) {
+    _opts = {}
+  }
   this.name = _name
+  this.json = _opts.json
+  if (this.json) {
+    this.treeView = new TreeView(_opts)
+  }
   this.view
-  _raw = _raw === undefined ? false : _raw
-  this.raw = _raw
 }
 
 DropdownPanel.prototype.update = function (_data) {
-  if (!this.view) {
-    return
-  }
-  if (_data) {
-    this.data = _data
-  }
-  this.view.querySelector('.dropdownpanel div.dropdowncontent').innerHTML = ''
-  if (!this.raw) {
-    var data = JSON.stringify(this.data, null, '\t')
-    if (!this.data || data === '[]' || data === '{}') {
-      this.data = ['Empty']
-    }
-    var div = document.createElement('div')
-    if (Array.isArray(this.data)) {
-      this.data.map(function (item, i) {
-        div.appendChild(yo`<div>${item}</div>`)
-      })
-    } else {
-      for (var k in this.data) {
-        var content = typeof this.data[k] === 'string' ? this.data[k] : JSON.stringify(this.data[k])
-        div.appendChild(yo`<div><div title=${k} style=${ui.formatCss(basicStyles.truncate, {display: 'inline-block', 'width': '10%'})} >${k}</div><div title=${content} style=${ui.formatCss(basicStyles.truncate, {display: 'inline-block', 'width': '78%'})} >${content}</div></div>`)
-      }
-    }
-    this.view.querySelector('.dropdownpanel div.dropdowncontent').appendChild(div)
+  if (this.view) {
+    this.view.querySelector('.dropdownpanel .dropdownrawcontent').innerText = JSON.stringify(_data, null, '\t')
     this.view.querySelector('.dropdownpanel button.btn').style.display = 'block'
-    this.view.querySelector('.dropdownpanel .dropdownrawcontent').innerText = data
-  } else {
-    this.view.querySelector('.dropdownpanel div.dropdowncontent').appendChild(this.data)
-    this.view.querySelector('.dropdownpanel button.btn').style.display = 'none'
+    if (this.json) {
+      this.treeView.update(_data)
+    }
   }
 }
 
+DropdownPanel.prototype.setContent = function (node) {
+  var parent = this.view.querySelector('.dropdownpanel div.dropdowncontent')
+  parent.replaceChild(node, parent.firstElementChild)
+}
+
 DropdownPanel.prototype.render = function (overridestyle) {
+  var content = yo`<div>Empty</div>`
+  if (this.json) {
+    content = this.treeView.render({})
+  }
   overridestyle === undefined ? {} : overridestyle
   var self = this
   var view = yo`<div>
@@ -55,7 +46,7 @@ DropdownPanel.prototype.render = function (overridestyle) {
     <div class='dropdownpanel' style=${ui.formatCss(styleDropdown.content)} style='display:none'>
       <button onclick=${function () { self.toggleRaw() }} style=${ui.formatCss(basicStyles.button, styleDropdown.copyBtn)} title='raw' class="btn fa fa-eye" type="button">
       </button>
-      <div style=${ui.formatCss(styleDropdown.inner, overridestyle)} class='dropdowncontent'><div>Empty</div></div>
+      <div style=${ui.formatCss(styleDropdown.inner, overridestyle)} class='dropdowncontent'>${content}</div>
       <div style=${ui.formatCss(styleDropdown.inner, overridestyle)} class='dropdownrawcontent' style='display:none'></div>
     </div>
     </div>`
diff --git a/src/ui/FullStoragesChanges.js b/src/ui/FullStoragesChanges.js
index 641b4e8879..9c4d4c6769 100644
--- a/src/ui/FullStoragesChanges.js
+++ b/src/ui/FullStoragesChanges.js
@@ -8,7 +8,7 @@ function FullStoragesChanges (_parent, _traceManager) {
   this.addresses = []
   this.view
   this.traceLength
-  this.basicPanel = new DropdownPanel('Full Storages Changes')
+  this.basicPanel = new DropdownPanel('Full Storages Changes', {json: true})
   this.init()
 }
 
diff --git a/src/ui/MemoryPanel.js b/src/ui/MemoryPanel.js
index e80166e31c..b48b59d49b 100644
--- a/src/ui/MemoryPanel.js
+++ b/src/ui/MemoryPanel.js
@@ -6,7 +6,11 @@ var yo = require('yo-yo')
 function MemoryPanel (_parent, _traceManager) {
   this.parent = _parent
   this.traceManager = _traceManager
-  this.basicPanel = new DropdownPanel('Memory')
+  this.basicPanel = new DropdownPanel('Memory', {
+    json: true,
+    css: {
+      'font-family': 'monospace'
+    }})
   this.init()
 }
 
diff --git a/src/ui/SolidityLocals.js b/src/ui/SolidityLocals.js
index afbca77a78..df2826f950 100644
--- a/src/ui/SolidityLocals.js
+++ b/src/ui/SolidityLocals.js
@@ -9,7 +9,7 @@ class SolidityLocals {
     this.parent = _parent
     this.internalTreeCall = internalTreeCall
     this.traceManager = _traceManager
-    this.basicPanel = new DropdownPanel('Solidity Locals')
+    this.basicPanel = new DropdownPanel('Solidity Locals', {json: true})
     this.init()
   }
 
diff --git a/src/ui/SolidityState.js b/src/ui/SolidityState.js
index bc4cc24e38..22303f8082 100644
--- a/src/ui/SolidityState.js
+++ b/src/ui/SolidityState.js
@@ -8,7 +8,7 @@ function SolidityState (_parent, _traceManager, _codeManager, _solidityProxy) {
   this.traceManager = _traceManager
   this.codeManager = _codeManager
   this.solidityProxy = _solidityProxy
-  this.basicPanel = new DropdownPanel('Solidity State')
+  this.basicPanel = new DropdownPanel('Solidity State', {json: true})
   this.init()
 }
 
diff --git a/src/ui/StackPanel.js b/src/ui/StackPanel.js
index dbf83dbb4d..0460c8a3ea 100644
--- a/src/ui/StackPanel.js
+++ b/src/ui/StackPanel.js
@@ -6,7 +6,7 @@ var yo = require('yo-yo')
 function StackPanel (_parent, _traceManager) {
   this.parent = _parent
   this.traceManager = _traceManager
-  this.basicPanel = new DropdownPanel('Stack')
+  this.basicPanel = new DropdownPanel('Stack', {json: true})
   this.init()
 }
 
diff --git a/src/ui/StepDetail.js b/src/ui/StepDetail.js
index ac752e5a51..88950e4e93 100644
--- a/src/ui/StepDetail.js
+++ b/src/ui/StepDetail.js
@@ -6,7 +6,7 @@ function StepDetail (_parent, _traceManager) {
   this.parent = _parent
   this.traceManager = _traceManager
 
-  this.basicPanel = new DropdownPanel('Step detail')
+  this.basicPanel = new DropdownPanel('Step detail', {json: true})
 
   this.detail = initDetail()
   this.view
diff --git a/src/ui/StoragePanel.js b/src/ui/StoragePanel.js
index f7f0c90a05..e0dd9612c9 100644
--- a/src/ui/StoragePanel.js
+++ b/src/ui/StoragePanel.js
@@ -5,7 +5,7 @@ var yo = require('yo-yo')
 function StoragePanel (_parent, _traceManager, _address) {
   this.parent = _parent
   this.traceManager = _traceManager
-  this.basicPanel = new DropdownPanel('Storage Changes')
+  this.basicPanel = new DropdownPanel('Storage Changes', {json: true})
   this.address = _address
   this.init()
   this.disabled = false
diff --git a/src/ui/TreeView.js b/src/ui/TreeView.js
new file mode 100644
index 0000000000..49df208ce9
--- /dev/null
+++ b/src/ui/TreeView.js
@@ -0,0 +1,70 @@
+'use strict'
+var yo = require('yo-yo')
+var style = require('./styles/treeView')
+var ui = require('../helpers/ui')
+
+class TreeView {
+
+  constructor (opts) {
+    function noop (node) {
+    }
+    this.beforeJsonNodeRendered = opts.beforeJsonNodeRendered || noop
+    this.beforeJsonValueRendered = opts.beforeJsonValueRendered || noop
+    this.view = null
+    this.cssLabel = ui.formatCss(opts.css || {}, style.label)
+    this.cssList = ui.formatCss(opts.css || {}, style.list)
+  }
+
+  render (json) {
+    var view = yo`<div>${this.renderProperties(json, true)}</div>`
+    if (!this.view) {
+      this.view = view
+    }
+    return view
+  }
+
+  update (json) {
+    if (this.view) {
+      yo.update(this.view, this.render(json), {onBeforeElUpdated: (fromEl, toEl) => {
+        toEl.style.display = fromEl.style.display
+        toEl.className = fromEl.className
+        return true
+      }})
+    }
+  }
+
+  renderObject (item, key, expand) {
+    var label
+    if (item instanceof Array || item instanceof Object) {
+      var properties = this.renderProperties(item, false)
+      label = yo`<span style=${this.cssLabel}><label style='width: 10px' id='caret'></label><label>${key} - ${properties.length} items</label></span>`
+      var list = yo`<ul style=${this.cssList}>${properties}</ol>`
+      list.style.display = expand ? 'block' : 'none'
+      label.firstElementChild.className = expand ? 'fa fa-caret-down' : 'fa fa-caret-right'
+      label.onclick = function () {
+        this.firstElementChild.className = this.firstElementChild.className === 'fa fa-caret-right' ? 'fa fa-caret-down' : 'fa fa-caret-right'
+        var list = this.parentElement.querySelector('ul')
+        list.style.display = list.style.display === 'none' ? 'block' : 'none'
+      }
+      if (this.beforeJsonNodeRendered) {
+        this.beforeJsonNodeRendered(label, item, key)
+      }
+      return yo`<li style=${this.cssList}>${label}${list}</li>`
+    } else {
+      label = yo`<label style=${this.cssLabel}>${key}</label>`
+      if (this.beforeJsonValueRendered) {
+        this.beforeJsonValueRendered(label, item, key)
+      }
+      return yo`<li style=${this.cssList}>${label}: <span style=${this.cssLabel} >${item}</span></li>`
+    }
+  }
+
+  renderProperties (json, expand) {
+    var properties = Object.keys(json).map((innerkey) => {
+      return this.renderObject(json[innerkey], innerkey, expand)
+    })
+    return properties
+  }
+}
+
+module.exports = TreeView
diff --git a/src/ui/TxBrowser.js b/src/ui/TxBrowser.js
index 1de5681882..1b929807aa 100644
--- a/src/ui/TxBrowser.js
+++ b/src/ui/TxBrowser.js
@@ -14,7 +14,7 @@ function TxBrowser (_parent) {
   this.txNumber
   this.view
   this.displayConnectionSetting = true
-  this.basicPanel = new DropdownPanel('Transaction')
+  this.basicPanel = new DropdownPanel('Transaction', {json: true})
   this.basicPanel.data = {}
   var self = this
   _parent.event.register('providerChanged', this, function (provider) {
@@ -34,8 +34,7 @@ function TxBrowser (_parent) {
 
 TxBrowser.prototype.setDefaultValues = function () {
   this.connectInfo = ''
-  this.basicPanel.data = {}
-  this.basicPanel.update()
+  this.basicPanel.update({})
   this.basicPanel.hide()
   this.updateWeb3Url(util.web3.currentProvider.host)
   if (this.view) {
@@ -86,8 +85,7 @@ TxBrowser.prototype.update = function (error, tx) {
       this.view.querySelector('#error').innerHTML = 'Cannot find transaction with reference. Block number: ' + this.blockNumber + '. Transaction index/hash: ' + this.txNumber
     }
   }
-  this.basicPanel.data = info
-  this.basicPanel.update()
+  this.basicPanel.update(info)
 }
 
 TxBrowser.prototype.updateWeb3Url = function (newhost) {
diff --git a/src/ui/VmDebugger.js b/src/ui/VmDebugger.js
index b4527df70a..c43abcede8 100644
--- a/src/ui/VmDebugger.js
+++ b/src/ui/VmDebugger.js
@@ -24,17 +24,16 @@ function VmDebugger (_parent, _traceManager, _codeManager, _solidityProxy, _call
   this.solidityLocals = new SolidityLocals(_parent, _traceManager, _callTree)
 
   /* Return values - */
-  this.returnValuesPanel = new DropdownPanel('Return Value')
+  this.returnValuesPanel = new DropdownPanel('Return Value', {json: true})
   this.returnValuesPanel.data = {}
   _parent.event.register('indexChanged', this.returnValuesPanel, function (index) {
     var self = this
     _traceManager.getReturnValue(index, function (error, returnValue) {
       if (error) {
-        self.data = [error]
+        self.update([error])
       } else if (_parent.currentStepIndex === index) {
-        self.data = [returnValue]
+        self.update([returnValue])
       }
-      self.update()
     })
   })
   /* Return values - */
diff --git a/src/ui/styles/dropdownPanel.js b/src/ui/styles/dropdownPanel.js
index b3c6ec5d87..3fe1c47c3e 100644
--- a/src/ui/styles/dropdownPanel.js
+++ b/src/ui/styles/dropdownPanel.js
@@ -13,8 +13,7 @@ module.exports = {
   },
   content: {
     'color': '#111111',
-    'width': '100%',
-    'font-family': 'monospace'
+    'width': '100%'
   },
   inner: {
     'padding': '2px',
diff --git a/src/ui/styles/treeView.js b/src/ui/styles/treeView.js
new file mode 100644
index 0000000000..b4c17c9efb
--- /dev/null
+++ b/src/ui/styles/treeView.js
@@ -0,0 +1,16 @@
+'use strict'
+module.exports = {
+  list: {
+    'list-style-type': 'none',
+    '-webkit-margin-before': '0px',
+    '-webkit-margin-after': '0px',
+    '-webkit-margin-start': '0px',
+    '-webkit-margin-end': '0px',
+    '-webkit-padding-start': '0px',
+    'margin-left': '10px'
+  },
+  label: {
+    'vertical-align': 'top',
+    'font-family': 'arial,sans-serif'
+  }
+}
diff --git a/test-browser/init.js b/test-browser/init.js
index 59d837f754..456d861420 100644
--- a/test-browser/init.js
+++ b/test-browser/init.js
@@ -32,7 +32,7 @@ function extendBrowser (browser) {
   }
 
   browser.assertStepDetail = function (vmtracestepinfo, stepinfo, addmemoryinfo, gasinfo, remaininggasinfo, loadedaddressinfo) {
-    assertPanel('#stepdetail', browser, ['vmtracestep' + vmtracestepinfo, 'executionstep' + stepinfo, 'addmemory' + addmemoryinfo, 'gas' + gasinfo, 'remaininggas' + remaininggasinfo, 'loadedaddress' + loadedaddressinfo])
+    assertPanel('#stepdetail', browser, ['vmtracestep:' + vmtracestepinfo, 'executionstep:' + stepinfo, 'addmemory:' + addmemoryinfo, 'gas:' + gasinfo, 'remaininggas:' + remaininggasinfo, 'loadedaddress:' + loadedaddressinfo])
     return browser
   }
 
@@ -141,8 +141,12 @@ function assertPanel (id, browser, value) {
     return ret
   }, [id, selector], function (returnValues) {
     value.map(function (item, index) {
-      var testValue = returnValues.value[index].replace(/\r\n/g, '').replace(/\t/g, '').replace(/\s/g, '')
-      browser.assert.equal(testValue, value[index])
+      if (returnValues.value.length) {
+        var testValue = returnValues.value[index].replace(/\r\n/g, '').replace(/\t/g, '').replace(/\s/g, '')
+        browser.assert.equal(testValue, value[index])
+      } else {
+        browser.assert.equal(item, '')
+      }
     })
   })
   return browser
diff --git a/test-browser/vmdebugger.js b/test-browser/vmdebugger.js
index da35da8d89..81eb29477b 100644
--- a/test-browser/vmdebugger.js
+++ b/test-browser/vmdebugger.js
@@ -63,21 +63,20 @@ function panels (browser) {
     .setValue('#txinput', '0x20ef65b8b186ca942fcccd634f37074dde49b541c27994fc7596740ef44cfd51')
     .click('#load')
     .click('#nextcall')
-    .assertStack(['0x', '0x60', '0x65', '0x38', '0x55', '0x60fe47b1'])
-    .pause(5000)
-    .assertStorageChanges(['0x000x38'])
-    .assertCallData(['0x60fe47b10000000000000000000000000000000000000000000000000000000000000038'])
-    .assertCallStack(['0x0d3a18d64dfe4f927832ab58d6451cecc4e517c5'])
-    .assertStackValue(1, '0x60')
-    .assertMemoryValue(6, '0x6060606040526040516020806045833981????R??Q????E?9?')
-    .assertMemoryValue(7, '0x7001604052808051906020019091905050???R??Q???????PP')
-    .assertMemoryValue(8, '0x805b806001016000600050819055505b50?????????P??UP?P')
+    .assertStack(['0:0x', '1:0x60', '2:0x65', '3:0x38', '4:0x55', '5:0x60fe47b1'])
+    .assertStorageChanges(['0x00:0x38'])
+    .assertCallData(['0:0x60fe47b10000000000000000000000000000000000000000000000000000000000000038'])
+    .assertCallStack(['0:0x0d3a18d64dfe4f927832ab58d6451cecc4e517c5'])
+    .assertStackValue(1, '1:0x60')
+    .assertMemoryValue(6, '0x60:60606040526040516020806045833981????R??Q????E?9?')
+    .assertMemoryValue(7, '0x70:01604052808051906020019091905050???R??Q???????PP')
+    .assertMemoryValue(8, '0x80:5b806001016000600050819055505b50?????????P??UP?P')
     .click('#intoforward') // CREATE
-    .assertStack(['Empty'])
-    .assertStorageChanges(['Empty'])
-    .assertMemory(['Empty'])
-    .assertCallData(['0x0000000000000000000000000000000000000000000000000000000000000000000000000000006060606040526040516020806045833981016040528080519060200190919050505b806001016000600050819055'])
-    .assertCallStack(['0x0d3a18d64dfe4f927832ab58d6451cecc4e517c5', '(ContractCreation-Step63)'])
+    .assertStack([''])
+    .assertStorageChanges([''])
+    .assertMemory([''])
+    .assertCallData(['0:0x0000000000000000000000000000000000000000000000000000000000000000000000000000006060606040526040516020806045833981016040528080519060200190919050505b806001016000600050819055'])
+    .assertCallStack(['0:0x0d3a18d64dfe4f927832ab58d6451cecc4e517c5', '1:(ContractCreation-Step63)'])
   return browser
 }