diff --git a/conf/gns3_server.conf b/conf/gns3_server.conf
index bcf188a1..ffab4ec8 100644
--- a/conf/gns3_server.conf
+++ b/conf/gns3_server.conf
@@ -61,8 +61,6 @@ sparse_memory_support = True
 ghost_ios_support = True
 
 [IOU]
-; iouyap executable path, default: search in PATH
-;iouyap_path = iouyap
 ; Path of your .iourc file. If not provided, the file is searched in $HOME/.iourc
 iourc_path = /home/gns3/.iourc
 ; Validate if the iourc license file is correct. If you turn this off and your licence is invalid IOU will not start and no errors will be shown.
diff --git a/gns3server/compute/iou/iou_vm.py b/gns3server/compute/iou/iou_vm.py
index 7f22d055..170d3560 100644
--- a/gns3server/compute/iou/iou_vm.py
+++ b/gns3server/compute/iou/iou_vm.py
@@ -76,6 +76,7 @@ class IOUVM(BaseNode):
         self._started = False
         self._nvram_watcher = None
         self._path = self.manager.get_abs_image_path(path)
+        self._license_check = True
 
         # IOU settings
         self._ethernet_adapters = []
@@ -358,6 +359,16 @@ class IOUVM(BaseNode):
             except OSError as e:
                 raise IOUError("Could not write the iourc file {}: {}".format(path, e))
 
+    @property
+    def license_check(self):
+
+        return self._license_check
+
+    @license_check.setter
+    def license_check(self, value):
+
+        self._license_check = value
+
     async def _library_check(self):
         """
         Checks for missing shared library dependencies in the IOU image.
@@ -379,11 +390,18 @@ class IOUVM(BaseNode):
         """
         Checks for a valid IOU key in the iourc file (paranoid mode).
         """
+
+        # license check is sent by the controller
+        if self.license_check is False:
+            return
+
         try:
-            license_check = self._config().getboolean("license_check", True)
+            # we allow license check to be disabled server wide
+            server_wide_license_check = self._config().getboolean("license_check", True)
         except ValueError:
             raise IOUError("Invalid licence check setting")
-        if license_check is False:
+
+        if server_wide_license_check is False:
             return
 
         config = configparser.ConfigParser()
diff --git a/gns3server/controller/__init__.py b/gns3server/controller/__init__.py
index 242f80a9..da316b52 100644
--- a/gns3server/controller/__init__.py
+++ b/gns3server/controller/__init__.py
@@ -54,9 +54,9 @@ class Controller:
         self._notification = Notification(self)
         self.gns3vm = GNS3VM(self)
         self.symbols = Symbols()
-
-        # FIXME: store settings shared by the different GUI will be replace by dedicated API later
-        self._settings = None
+        self._iou_license_settings = {"iourc_content": "",
+                                      "license_check": True}
+        self._config_loaded = False
         self._appliances = {}
         self._appliance_templates = {}
         self._appliance_templates_etag = None
@@ -150,6 +150,7 @@ class Controller:
             raise aiohttp.web.HTTPConflict(text="Cannot create new appliance: key '{}' is missing for appliance ID '{}'".format(e, appliance_id))
         self._appliances[appliance.id] = appliance
         self.save()
+        self.notification.controller_emit("appliance.created", appliance.__json__())
         return appliance
 
     def get_appliance(self, appliance_id):
@@ -173,13 +174,12 @@ class Controller:
         :param appliance_id: appliance identifier
         """
 
-        appliance = self._appliances.get(appliance_id)
-        if not appliance:
-            raise aiohttp.web.HTTPNotFound(text="Appliance ID {} doesn't exist".format(appliance_id))
+        appliance = self.get_appliance(appliance_id)
         if appliance.builtin:
             raise aiohttp.web.HTTPConflict(text="Appliance ID {} cannot be deleted because it is a builtin".format(appliance_id))
         self._appliances.pop(appliance_id)
         self.save()
+        self.notification.controller_emit("appliance.deleted", appliance.__json__())
 
     def load_appliances(self):
 
@@ -231,7 +231,7 @@ class Controller:
                                                         user=server_config.get("user", ""),
                                                         password=server_config.get("password", ""),
                                                         force=True)
-        except aiohttp.web.HTTPConflict as e:
+        except aiohttp.web.HTTPConflict:
             log.fatal("Cannot access to the local server, make sure something else is not running on the TCP port {}".format(port))
             sys.exit(1)
         for c in computes:
@@ -276,14 +276,13 @@ class Controller:
         Save the controller configuration on disk
         """
 
-        # We don't save during the loading otherwise we could lost stuff
-        if self._settings is None:
+        if self._config_loaded is False:
             return
 
         controller_settings = {"computes": [],
-                               "settings": self._settings,
                                "appliances": [],
                                "gns3vm": self.gns3vm.__json__(),
+                               "iou_license": self._iou_license_settings,
                                "appliance_templates_etag": self._appliance_templates_etag,
                                "version": __version__}
 
@@ -321,14 +320,8 @@ class Controller:
                 controller_settings = json.load(f)
         except (OSError, ValueError) as e:
             log.critical("Cannot load configuration file '{}': {}".format(self._config_file, e))
-            self._settings = {}
             return []
 
-        if "settings" in controller_settings and controller_settings["settings"] is not None:
-            self._settings = controller_settings["settings"]
-        else:
-            self._settings = {}
-
         # load the appliances
         if "appliances" in controller_settings:
             for appliance_settings in controller_settings["appliances"]:
@@ -345,9 +338,14 @@ class Controller:
         if "gns3vm" in controller_settings:
             self.gns3vm.settings = controller_settings["gns3vm"]
 
+        # load the IOU license settings
+        if "iou_license" in controller_settings:
+            self._iou_license_settings = controller_settings["iou_license"]
+
         self._appliance_templates_etag = controller_settings.get("appliance_templates_etag")
         self.load_appliance_templates()
         self.load_appliances()
+        self._config_loaded = True
         return controller_settings.get("computes", [])
 
     async def load_projects(self):
@@ -528,26 +526,6 @@ class Controller:
                         log.warning("Cannot load appliance template {} ('{}'): missing key {}".format(vm["appliance_id"], vm.get("name", "unknown"), e))
                         continue
 
-                self._settings = {}
-
-    @property
-    def settings(self):
-        """
-        Store settings shared by the different GUI will be replace by dedicated API later. Dictionnary
-        """
-
-        return self._settings
-
-    @settings.setter
-    def settings(self, val):
-
-        self._settings = val
-        self._settings["modification_uuid"] = str(uuid.uuid4())  # We add a modification id to the settings to help the gui to detect changes
-        self.save()
-        self.load_appliance_templates()
-        self.load_appliances()
-        self.notification.controller_emit("settings.updated", val)
-
     async def add_compute(self, compute_id=None, name=None, force=False, connect=True, **kwargs):
         """
         Add a server to the dictionary of compute servers controlled by this controller
@@ -783,6 +761,14 @@ class Controller:
 
         return self._appliances
 
+    @property
+    def iou_license(self):
+        """
+        :returns: The dictionary of IOU license settings
+        """
+
+        return self._iou_license_settings
+
     def projects_directory(self):
 
         server_config = Config.instance().get_section_config("Server")
diff --git a/gns3server/controller/appliance.py b/gns3server/controller/appliance.py
index 5616bf77..ecc304ce 100644
--- a/gns3server/controller/appliance.py
+++ b/gns3server/controller/appliance.py
@@ -96,8 +96,11 @@ class Appliance:
 
     def update(self, **kwargs):
 
-        #TODO: do not update appliance_id, builtin or appliance_type
         self._settings.update(kwargs)
+        from gns3server.controller import Controller
+        controller = Controller.instance()
+        controller.notification.controller_emit("appliance.updated", self.__json__())
+        controller.save()
 
     def __json__(self):
         """
diff --git a/gns3server/controller/node.py b/gns3server/controller/node.py
index 95227606..2e9047bc 100644
--- a/gns3server/controller/node.py
+++ b/gns3server/controller/node.py
@@ -271,16 +271,17 @@ class Node:
         if self._label is None:
             # Apply to label user style or default
             try:
-                style = qt_font_to_style(self._project.controller.settings["GraphicsView"]["default_label_font"],
-                                         self._project.controller.settings["GraphicsView"]["default_label_color"])
+                style = None  # FIXME: allow configuration of default label font & color on controller
+                #style = qt_font_to_style(self._project.controller.settings["GraphicsView"]["default_label_font"],
+                #                         self._project.controller.settings["GraphicsView"]["default_label_color"])
             except KeyError:
-                style = "font-size: 10;font-familly: Verdana"
+                style = "font-family: TypeWriter;font-size: 10.0;font-weight: bold;fill: #000000;fill-opacity: 1.0;"
 
             self._label = {
                 "y": round(self._height / 2 + 10) * -1,
                 "text": html.escape(self._name),
-                "style": style,
-                "x": None,  # None: mean the client should center it
+                "style": style,  # None: means the client will apply its default style
+                "x": None,  # None: means the client should center it
                 "rotation": 0
             }
 
@@ -483,11 +484,11 @@ class Node:
         try:
             # For IOU we need to send the licence everytime
             if self.node_type == "iou":
-                try:
-                    licence = self._project.controller.settings["IOU"]["iourc_content"]
-                except KeyError:
+                license_check = self._project.controller.iou_license.get("license_check", True)
+                iourc_content = self._project.controller.iou_license.get("iourc_content", None)
+                if license_check and not iourc_content:
                     raise aiohttp.web.HTTPConflict(text="IOU licence is not configured")
-                await self.post("/start", timeout=240, data={"iourc_content": licence})
+                await self.post("/start", timeout=240, data={"license_check": license_check, "iourc_content": iourc_content})
             else:
                 await self.post("/start", data=data, timeout=240)
         except asyncio.TimeoutError:
diff --git a/gns3server/handlers/api/controller/appliance_handler.py b/gns3server/handlers/api/controller/appliance_handler.py
index 06e6f56c..4c3115f7 100644
--- a/gns3server/handlers/api/controller/appliance_handler.py
+++ b/gns3server/handlers/api/controller/appliance_handler.py
@@ -103,6 +103,11 @@ class ApplianceHandler:
 
         controller = Controller.instance()
         appliance = controller.get_appliance(request.match_info["appliance_id"])
+        # Ignore these because we only use them when creating a appliance
+        request.json.pop("appliance_id", None)
+        request.json.pop("appliance_type", None)
+        request.json.pop("compute_id", None)
+        request.json.pop("builtin", None)
         appliance.update(**request.json)
         response.set_status(200)
         response.json(appliance)
diff --git a/gns3server/handlers/api/controller/gns3_vm_handler.py b/gns3server/handlers/api/controller/gns3_vm_handler.py
index 5371e3d0..d1c56b6a 100644
--- a/gns3server/handlers/api/controller/gns3_vm_handler.py
+++ b/gns3server/handlers/api/controller/gns3_vm_handler.py
@@ -15,12 +15,10 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from aiohttp.web import HTTPConflict
 from gns3server.web.route import Route
 from gns3server.controller import Controller
 from gns3server.schemas.gns3vm import GNS3VM_SETTINGS_SCHEMA
 
-
 import logging
 log = logging.getLogger(__name__)
 
diff --git a/gns3server/handlers/api/controller/server_handler.py b/gns3server/handlers/api/controller/server_handler.py
index a7422816..ae1160c4 100644
--- a/gns3server/handlers/api/controller/server_handler.py
+++ b/gns3server/handlers/api/controller/server_handler.py
@@ -19,6 +19,7 @@ from gns3server.web.route import Route
 from gns3server.config import Config
 from gns3server.controller import Controller
 from gns3server.schemas.version import VERSION_SCHEMA
+from gns3server.schemas.iou_license import IOU_LICENSE_SETTINGS_SCHEMA
 from gns3server.version import __version__
 
 from aiohttp.web import HTTPConflict, HTTPForbidden
@@ -102,37 +103,31 @@ class ServerHandler:
         response.json({"version": __version__})
 
     @Route.get(
-        r"/settings",
-        description="Retrieve gui settings from the server. Temporary will we removed in later release")
-    async def read_settings(request, response):
-
-        settings = None
-        while True:
-            # The init of the server could take some times
-            # we ensure settings are loaded before returning them
-            settings = Controller.instance().settings
-
-            if settings is not None:
-                break
-            await asyncio.sleep(0.5)
-        response.json(settings)
-
-    @Route.post(
-        r"/settings",
-        description="Write gui settings on the server. Temporary will we removed in later releases",
+        r"/iou_license",
+        description="Get the IOU license settings",
         status_codes={
-            201: "Settings saved"
+            200: "IOU license settings returned"
+        },
+        output_schema=IOU_LICENSE_SETTINGS_SCHEMA)
+    def show(request, response):
+
+        response.json(Controller.instance().iou_license)
+
+    @Route.put(
+        r"/iou_license",
+        description="Update the IOU license settings",
+        input_schema=IOU_LICENSE_SETTINGS_SCHEMA,
+        output_schema=IOU_LICENSE_SETTINGS_SCHEMA,
+        status_codes={
+            201: "IOU license settings updated"
         })
-    def write_settings(request, response):
-        controller = Controller.instance()
-        if controller.settings is None:  # Server is not loaded ignore settings update to prevent buggy client sync issue
-            return
-        try:
-            controller.settings = request.json
-            #controller.save()
-        except (OSError, PermissionError) as e:
-            raise HTTPConflict(text="Can't save the settings {}".format(str(e)))
-        response.json(controller.settings)
+    async def update(request, response):
+
+        controller = Controller().instance()
+        iou_license = controller.iou_license
+        iou_license.update(request.json)
+        controller.save()
+        response.json(iou_license)
         response.set_status(201)
 
     @Route.post(
diff --git a/gns3server/schemas/appliance.py b/gns3server/schemas/appliance.py
index 2cbb9ea8..408e33c4 100644
--- a/gns3server/schemas/appliance.py
+++ b/gns3server/schemas/appliance.py
@@ -58,13 +58,16 @@ APPLIANCE_OBJECT_SCHEMA = {
 }
 
 APPLIANCE_CREATE_SCHEMA = copy.deepcopy(APPLIANCE_OBJECT_SCHEMA)
+
+# create schema
 # these properties are not required to create an appliance
 APPLIANCE_CREATE_SCHEMA["required"].remove("appliance_id")
 APPLIANCE_CREATE_SCHEMA["required"].remove("compute_id")
 APPLIANCE_CREATE_SCHEMA["required"].remove("default_name_format")
 APPLIANCE_CREATE_SCHEMA["required"].remove("symbol")
-APPLIANCE_UPDATE_SCHEMA = copy.deepcopy(APPLIANCE_CREATE_SCHEMA)
-#APPLIANCE_UPDATE_SCHEMA["additionalProperties"] = False
+
+# update schema
+APPLIANCE_UPDATE_SCHEMA = copy.deepcopy(APPLIANCE_OBJECT_SCHEMA)
 del APPLIANCE_UPDATE_SCHEMA["required"]
 
 APPLIANCE_USAGE_SCHEMA = {
diff --git a/gns3server/schemas/iou.py b/gns3server/schemas/iou.py
index 3243c890..8bad7a9e 100644
--- a/gns3server/schemas/iou.py
+++ b/gns3server/schemas/iou.py
@@ -104,6 +104,10 @@ IOU_START_SCHEMA = {
         "iourc_content": {
             "description": "Content of the iourc file. Ignored if Null",
             "type": ["string", "null"]
+        },
+        "license_check": {
+            "description": "Whether the license should be checked",
+            "type": "boolean"
         }
     }
 }
diff --git a/tests/handlers/api/controller/test_settings.py b/gns3server/schemas/iou_license.py
similarity index 54%
rename from tests/handlers/api/controller/test_settings.py
rename to gns3server/schemas/iou_license.py
index a87df472..4b2262cf 100644
--- a/tests/handlers/api/controller/test_settings.py
+++ b/gns3server/schemas/iou_license.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 #
-# Copyright (C) 2015 GNS3 Technologies Inc.
+# Copyright (C) 2018 GNS3 Technologies Inc.
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -15,19 +15,19 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-"""
-This test suite check /version endpoint
-It's also used for unittest the HTTP implementation.
-"""
-
-from gns3server.config import Config
-
-
-def test_settings(http_controller):
-    query = {"test": True}
-    response = http_controller.post('/settings', query, example=True)
-    assert response.status == 201
-    response = http_controller.get('/settings', example=True)
-    assert response.status == 200
-    assert response.json["test"] is True
-    assert response.json["modification_uuid"] is not None
+IOU_LICENSE_SETTINGS_SCHEMA = {
+    "$schema": "http://json-schema.org/draft-04/schema#",
+    "description": "IOU license",
+    "type": "object",
+    "properties": {
+        "iourc_content": {
+            "type": "string",
+            "description": "Content of iourc file"
+        },
+        "license_check": {
+            "type": "boolean",
+            "description": "Whether the license must be checked or not",
+        },
+    },
+    "additionalProperties": False
+}
diff --git a/gns3server/schemas/label.py b/gns3server/schemas/label.py
index eae97417..eb5c2de1 100644
--- a/gns3server/schemas/label.py
+++ b/gns3server/schemas/label.py
@@ -20,11 +20,11 @@ LABEL_OBJECT_SCHEMA = {
     "properties": {
         "text": {"type": "string"},
         "style": {
-            "description": "SVG style attribute",
-            "type": "string"
+            "description": "SVG style attribute. Apply default style if null",
+            "type": ["string", "null"]
         },
         "x": {
-            "description": "Relative X position of the label. If null center it",
+            "description": "Relative X position of the label. Center it if null",
             "type": ["integer", "null"]
         },
         "y": {
diff --git a/tests/conftest.py b/tests/conftest.py
index bb24dca5..2c4260c5 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -201,7 +201,7 @@ def controller(tmpdir, controller_config_path):
     Controller._instance = None
     controller = Controller.instance()
     controller._config_file = controller_config_path
-    controller._settings = {}
+    controller._config_loaded = True
     return controller
 
 
diff --git a/tests/controller/test_controller.py b/tests/controller/test_controller.py
index 18e87fd6..0d99a534 100644
--- a/tests/controller/test_controller.py
+++ b/tests/controller/test_controller.py
@@ -35,7 +35,7 @@ def test_save(controller, controller_config_path):
         data = json.load(f)
         assert data["computes"] == []
         assert data["version"] == __version__
-        assert data["settings"] == {}
+        assert data["iou_license"] == controller.iou_license
         assert data["gns3vm"] == controller.gns3vm.__json__()
 
 
@@ -53,12 +53,10 @@ def test_load_controller_settings(controller, controller_config_path, async_run)
             "compute_id": "test1"
         }
     ]
-    data["settings"] = {"IOU": {"test": True}}
     data["gns3vm"] = {"vmname": "Test VM"}
     with open(controller_config_path, "w+") as f:
         json.dump(data, f)
     assert len(async_run(controller._load_controller_settings())) == 1
-    assert controller.settings["IOU"]
     assert controller.gns3vm.settings["vmname"] == "Test VM"
 
 
@@ -199,13 +197,6 @@ def test_import_remote_gns3vm_1_x(controller, controller_config_path, async_run)
     assert controller.gns3vm.settings["vmname"] == "http://127.0.0.1:3081"
 
 
-def test_settings(controller):
-    controller._notification = MagicMock()
-    controller.settings = {"a": 1}
-    controller._notification.controller_emit.assert_called_with("settings.updated", controller.settings)
-    assert controller.settings["modification_uuid"] is not None
-
-
 def test_load_projects(controller, projects_dir, async_run):
     controller.save()
 
diff --git a/tests/controller/test_node.py b/tests/controller/test_node.py
index a80bc9a1..715cdbbf 100644
--- a/tests/controller/test_node.py
+++ b/tests/controller/test_node.py
@@ -269,7 +269,7 @@ def test_symbol(node, symbols_dir):
     assert node.height == 71
     assert node.label["x"] is None
     assert node.label["y"] == -40
-    assert node.label["style"] == "font-size: 10;font-familly: Verdana"
+    assert node.label["style"] == None#"font-family: TypeWriter;font-size: 10.0;font-weight: bold;fill: #000000;fill-opacity: 1.0;"
 
     shutil.copy(os.path.join("gns3server", "symbols", "cloud.svg"), os.path.join(symbols_dir, "cloud2.svg"))
     node.symbol = "cloud2.svg"
@@ -298,7 +298,7 @@ def test_label_with_default_label_font(node):
 
     node._label = None
     node.symbol = ":/symbols/dslam.svg"
-    assert node.label["style"] == "font-family: TypeWriter;font-size: 10;font-weight: bold;fill: #ff0000;fill-opacity: 1.0;"
+    assert node.label["style"] == None #"font-family: TypeWriter;font-size: 10;font-weight: bold;fill: #ff0000;fill-opacity: 1.0;"
 
 
 def test_update(node, compute, project, async_run, controller):
@@ -405,9 +405,9 @@ def test_start_iou(compute, project, async_run, controller):
     with pytest.raises(aiohttp.web.HTTPConflict):
         async_run(node.start())
 
-    controller.settings["IOU"] = {"iourc_content": "aa"}
+    controller._iou_license_settings = {"license_check": True, "iourc_content": "aa"}
     async_run(node.start())
-    compute.post.assert_called_with("/projects/{}/iou/nodes/{}/start".format(node.project.id, node.id), timeout=240, data={"iourc_content": "aa"})
+    compute.post.assert_called_with("/projects/{}/iou/nodes/{}/start".format(node.project.id, node.id), timeout=240, data={"license_check": True, "iourc_content": "aa"})
 
 
 def test_stop(node, compute, project, async_run):