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We are pleased to announce that Nest Link is now working properly. 

The problem was caused by the obscure "spec" of Firebase which only allowed a single user to authenticate in a given Firebase server even it appears that multiple instances of Firebase clients are created and isolated. Single user operation is a reasonable assumption for a mobile app, but it is definitely not reasonable assumption when Firebase releases a client for node.js which is used to develop a web server. This "spec" was not clearly described in Firebase documentation which caused confusion for other developers too.

So, until today, Nest Link was working only for the last user that used it, because Firebase node.js client only allows one user to be authenticated to a given server at any given time. 

We have scrambled to replace the Firebase node.js client with our own that uses open standard REST streaming, which Nest also supports but with more limitations than with the native Firebase code.  

Now we have confirmed that the Nest Link seems to be working simultaneously for everybody. 

If you have given up on the Nest Link and associated KumoApp algorithms before, we encourage you to give them another try. No special step is needed to make this fix take effect on your side.

You can now link Dropcam to your Wireless Tag account. This will allow you to
    • Take snapshots and save them at the full 720p resolution
    • Turn streaming on and off
    • Do the above from KumoApp recipe. For example, you can write a KumoApp to take a burst of photo (at about 2fps) when PIR Kumo Sensor or Motion Sensor Tag detected movement, or door is open, and then email to you. You can also schedule pictures to be taken at certain interval, or any logical combination you can write using the KumoApp Javascript engine.
      • No more false activity alerts from the less-than-perfect motion detector on your Dropcam!

This is similar to the way you can link Nest Thermostats and WeMo switches. It may seem unnecessary to be able to control them from the Wireless Tags app when WeMo, Nest and Dropcam already have their own mobile apps, but it is when you start to write (or install existing) KumoApps like below, that this will all make sense:

Lastly, if you ever wanted to link Wireless Tag with other stuffs than WeMo, Nest, Dropcam or Philips Hue that can now be done with KumoApp, try our unpublished IFTTT channel. It is currently under review by IFTTT staffs for quality assurance. But many of Wireless Tag enthusiasts have already tried it (even before this article!) and we have already received some good feedback.

Using the latest Android app (version 2.2) and iOS app (version 2.3.1 and above, which should be released in AppStore next week) you can link WeMo switches as a tag to allow automation through KumoApp. These KumoApps have been made available (you can install them or make your own version based on their source code, once you link your WeMo switch):

  • When any of the PIR sensor detected motion, turn on Wemo, when all times out, turn off Wemo
  • When any of the PIR sensor detected motion while all of specified phone are away from home, turn on Wemo (makes potential thieves think you are at home)
  • When more than specified number of PIR sensors detected motion, turn on Wemo, when the number falls below, turn off Wemo
  • When any of the door is opened, turn on Wemo
  • When any motion sensor tag is moved (when they are armed), turn on Wemo
  • When any motion sensor tag is moved (when they are armed), and while all of specified phone are away from home, turn on Wemo
  • When any of specified phones enters region, turn on Wemo switches
  • When temperature is too high, turn on Wemo, when temperature is back to normal, turn off Wemo
  • When temperature is too low, turn on Wemo, when temperature is back to normal, turn off Wemo
  • When all specified phones leave region, turn off Wemo switches

Linking WeMo switch is very similar to linking Nest Thermostat. After you have connected you iOS or Android device to the same local WiFi network your WeMo device is on, launch the WirelessTag app and click the "+ Associate" button. If the app can find a WeMo switch on your local WiFi, a green "Link WeMo" button will show up (you may have to give the app about 10 second after launch for it to find your WeMo devices). Linking WeMo device function is not available from Web Interface on laptops, but once linked, WeMo device can be controlled from the Web Interface as well as from KumoApp. 


UPDATE: With latest version of Android app 2.3.5 we have improved the reliability of the app finding WeMo switches on your network. You need to connect the Android to your local WiFi for the green "Link Wemo" button to show up. The iOS app 2.3.1 is still under AppStore review as some issues were discovered during review and delayed the release. You can join the Test Flight program to try out this iOS app version and any future pre-release versions.


Over the next few months, our priority will be to integrate Wireless Tags with as many Internet connected products and services as we can think of. 

As part of that plan, we are pleased to announce today that we now support OAuth 2 for linking our API. 

Get started

OAuth 2 is used to link 3rd party web services without giving up account login and password to that 3rd party. It is used by everybody from Nest official API to Twitter to Facebook login. 

By supporting OAuth 2, we make it easy for people to develop "apps" that use our API. 

We will be developing one of such apps to integrate us with Zapier very soon. 


The Android app now uses native OpenGL based graphing code to handle large amount of data points (e.g. plotting data from up to 255 tags on the same screen) and to allow smooth zooming/panning by touch gestures. Also the same code for iOS app graphing has been ported to Android for dynamic download of raw data points from cloud as graph is zoomed or panned, so even if millions of data points are captured, the graph will load instantly.

You are able to download the entire data as CSV file using the download button at upper right corner (to email, Google Drive, Drop box etc) or share the displayed graph as PNG file using installed photo sharing apps (Email, facebook, picasa etc) using the share button.  

Install it from Google Play

If you are mainly using the Web interface with mouse (on Mac or PC), you can now drag & drop each tag entry to change the order they are displayed. The sorting you did is automatically remembered by the cloud and be synchronized across devices (e.g. the tag list on the iOS device will appear in the same order).



We have noticed that again there has been more "Operation timed out" errors for app-to-tag communication, like arm/disarm, apply configuration changes or beep. Upon investigation using network packet analysis, we have blocked several IP addresses that were flooding our server with invalid IP packets. Also we have lowered the "ping frequency" of tag managers to reduce the amount of non-essential traffic. As a result, now the latency from app to tag manager is much shorter than before (always <1s and without timeout error) and the majority of app-to-tag communication latency is now from the tag radio receiver delay, which is programmable from Wireless Settings and in trade-off with tag battery life. 

You can test the intrinsic latency from app to tag manager, by using Debug Console (after you login) where you can use the "Get" button to read tag manager register values chosen at the drop down, e.g. AFSKCTRL, RSSI, etc. note the result only appears after 2nd read.)  The delay from clicking "Get" button to the result appearing, equals to the delay of app commands like "beep" minus the actual tag radio receiver delay

UPDATE (Aug 29) We have switched to a completely new IRC server software that uses "Windows I/O Completion Port" to handle large number of connections. These timeout issues seem to be completely gone now. 


KumoApps are supposed to allow defining triggers that use location of iPhones and iPads (, such as "Arm motion sensors when all phones are away from home, disarm when any enters near home." and "Turn off AC/heat when all devices exit a region". However due to bug in the iOS app, this did not really work at all until now.

We are pleased to announce that with the latest iOS app release, these KumoApp will start to work. When you stop and restart the KumoApp, the holder of each device you have chosen will receive a push message that asks for permission to start monitoring region for the KumoApp. The holder would tap on the notification to open the app to start monitoring the region configured with the KumoApp. Once monitoring is started, even if the iOS app is closed, KumoApp will be triggered upon entry and exit of the specified region.

There are still several known issues which will be fixed in the next release:

  • If you receive "error start monitoring region, kCLErrorDomain error 4", you need to go to home screen, open the "Settings" app and then "General" then "Background app refresh" and disable and re-enable the toggle switch next to "Kumostat" app.
  • Sometimes you will receive "error start monitoring region, kCLErrorDomain error 5". This error can be safely ignored.

Try linking your Nest Thermostat and install the "Turn off AC/heat when all devices exit a region" today.

During the past few weeks, user initiated commands like "ping" "beep" "arm" "disarm" resulted in "Operation timed out" error more often than what we consider normal (2~3% of the time). This problem was related to a background process we were running to implement out-range/in-range notification feature. A spike in server issued command to search for out of range tags caused over capacity in one communication channel, resulting "time out" error for regular user commands. We have resolved this issued by controlling the rate such background search command is sent out.  If you still experience "time out" error please report it in the forum or email to

The capability to link Nest Thermostats as tags has been added in the Web / Android app. To link, from simply click "+ Add a New Tag" then "Link Nest Thermostats". Once linked, the thermostat is accessible also from current iOS app, but you may experience some quirks. Complete Nest link support will appear in the next iOS app release (approx. 1 week from now). 

Now you can

  • Set heat/cool targets, home/away, fan on/off from the web/app interface like shown in
  • Use temperature events @another sensor tag to control Nest. The lower/upper target temperature at Nest will automatically move so as to regulate the temperature at specified sensor tag within the "comfort zone" (this will automatically control the too-hot/too-low temperature at the chosen tag). Simply choose the tag at "Set at" drop-down. 
    Once you set the "target" back to Nest itself, the target temperature at Nest will be automatically restored to the value on "comfort zone" slider. 
  • Once Nest is linked, a whole new range of KumoApp becomes available for installation, such as "Turn off heat/AC ( equivalent to setting to "away" in Nest when "auto-away" is not used, and to "off" with "auto-away" on ) when window is open", "turn on heat/AC (same as setting to "home" or "heat-cool" depending on if auto-away is used) when my iPhone gets close to home". With soon-be-available PIR and Reed sensors, you will be able to install/write your own KumoApps like "when PIR detected motion, set to home, or use temperature events at the PIR sensor to control thermostat.  "When sliding door/window is open, set to "away" etc. 
  • "Upper/lower target temperatures" at Nest are just like the upper/lower temperature thresholds in regular tags with temperature monitoring enabled. When these thresholds are crossed, you can specify email/tweets/push notifications to be sent or custom URL to be called. You can even use these events to control another Nest thermostat.

No amount of internal testing can substitute feedback from actual users. Please submit bug reports at the forum or email to We appreciate your feedback.


First production batch of PIR and Reed sensor will arrive in a few days; our plastic casing factory in Anaheim has the injection mold and should be able to run production in next few days when machine slot opens. We plan to gradually ramp up the production. 


We have updated the Web interface and Android app to include the new "events view". Same update will appear in iOS app 2.1.12 and later when it gets released. 

Access this feature by clicking the coral/pink "Events" button or directly from if you are logged in. 

This view lists all events from all tags including motion, temperature too low/too high, humidity/moisture too low/too high and water detected/no longer detected in one place. Just like a twitter page, as you scroll down more and more older events are dynamically downloaded from server. 

Using the search/filter text box at the top of the page, you can quickly filter the results, for example if you only want to see moved events, type "moved". If you only want to see events from certain tags, type the first few letters of the tag's name. 

We realize a lot of our customers were running "Log every update" KumoApp just to get a report of all events from all tags in one place. We hope this new feature will meet these demands.

EDIT (6/24/14): in the current version iOS app 2.2.2 this event view is present, but its behavior is buggy. This will be fixed in app version 2.2.3. 

Due to unexpected long lead time of a key component in the Water/moisture sensor, in the worst case we will only get restocked of this sensor middle~end of November. We still have about 2~3 months worth of stock. We have temporarily increased the price from $15 to $21 to even out sales of remaining stock, so more people get a chance to try this sensor. Once we get restocked, we will bring the price down to a normal level.

We are aware the current version iOS app crashes when opening Account Options. A fix (2.1.7) has already been submitted to App Store for review, it should become available in approximately 3 days.Meanwhile, please use the Web interface to change login email and password, and other account options such as adding tag managers and limited user accounts, which are not supported using the iOS app anyway.  UPDATES: This has been fixed in 2.1.7 that was released today (May 23).

Also we are aware if you live outside of USA/Canada, the new native iOS app temperature graph had been crashing for 2.0.x and 2.1.x. This has just been fixed from the server side, no app update is necessary. It was due to the server auto-adjusting date format to native format used in your culture/country, and this confused date parsing code in the iOS app code. You will still get localized date format if you access the temperature graph from Web, only when the data is access by the graph code in the app that the server stops to localize the date format.

We have noticed that for some Tag Managers the DNS name look-up for "" can take very long, sometimes over 10 seconds. During the lookup, the tag manager orange up arrow will stay lit and tag manager cannot respond to user commands. We just made a change in the server side (that retroactively becomes effective on all existing long range tag managers with rev>5) to configure your Tag Managers to only do the name look-up once at power on, not each time sending new tag update. This should result in significant reduction in the time the orange up arrow light stays on, and hence a much more responsive tag manager, especially when the number of tags is large and auto-update interval is short.

You don't need to do anything for this change to be applied to your Tag Manager, but a power cycle will not hurt to make sure this change has been applied.

For long range tags, until now the system were automatically enabling "Low Power Receive Mode" when it determines the sensor tag is well within range and frequency drift is well within limit (so frequency calibration is not needed,) and disabling it when the signal strength drops or frequency drifts.

The Low Power Receive Mode works well only if the radio channel has been quiet (no user command to other tags) for at least 10 seconds prior to sending a command to the tag with the mode enabled. If immediately following a command to another tag, a command is sent to the tag, there will be longer than usual delay, even "tag did not respond" error.

Although this mode will increase stand-by battery life, we have determined that it should only be enabled if the user chooses to. Effective immediately the system will respect user's setting and will not attempt to automatically enable this mode. If you want to take advantage of this mode to increase battery life, and understand its above limitations, please enable this mode manually from "More..." > "Receiver Mode" (web interface) or "Gear icon" > "Receiver Mode" (iOS app).

User Interface SDK now available for download: This kit allows you to quickly build and run your own customized user interface in your favorite web browser to access your Tags and Tag Managers, in ways not possible otherwise.

For example, just open the file named "index.html" inside the downloaded zip file, find the auto-update drop-down
  <select data-inline=1 name="updateInterval" id="updateInterval">
    <option value="30">Every 30 seconds (worst battery life)</option>
    <option value="60">Every 1 minute</option>
and add an entry such as
    <option value="86400">Once a day</option>
Save the file, and open Mongoose (use included Windows version or download Mac/Linux version or build your own) to immediately try your own user interface on your account at to access your Tag managers and tags.

Here is another example: Open "styles/client.js", locate the function
function createTagList() {
    url: WSROOT + "ethClient.asmx/GetTagList",
      success: function (retval, textStatus) {
      for (var i = 0; i < retval.d.length; i++) {
This code calls our JSON API to retrieve information about the tags as Javascript objects.
Add the line
      retval.d.sort(function(a,b){ return b.lastComm-a.lastComm; });
just before the for loop. This simple change will make the most recently updated tag always come at the top of the list. Instead of lastComm, you can sort using other properties like signal strength, status, battery voltages... see for available properties in the returned data object.

These are just simple examples. You just need some basic knowledge of JavaScript, HTML and imagination.
When you are done developing your own Web UI, just zip the entire folder and share with others. We are excited to learn what kind of unique user interface you can come up with.
Based on customers feedback we are releasing a high-end variant of motion sensor tag with accurate temperature and humidity sensor. A lot of our customers were using sensor tags to monitor temperature, despite the fact our regular sensor tags were not designed for that purpose, and only had inaccurate analog temperature sensor. We realize that the ADC (analog-to-digital converter) and reference we use in a regular sensor tag randomly produce a glitch which causes false too hot/cold notification. While we made changes on the server side so it can filter out this glitch (when this glitch happens, the internal voltage reference reading will also suddenly be higher, so using this reading we can discard the glitch reading) without discarding the data when temperature jumps in reality, the new variant will resolve this problem completely. 

The new variant of motion sensor tags use high-end digital temperature/air humidity sensor, and are specially designed to take accurate temperature and air humidity logs and provide reliable notifications of too hot/cold/humid/dry. They do pretty much same or even better job as products like Netatmo Weather Station, with a lot more compact form factor and at much lower price, not to mention the extra features of a regular motion sensor tags (beep to locate, motion detection/logging). You can store unlimited amount of temperature/humidity data (for regular tags data older than 2 months are removed from server).

Check out a demo video showing the new graphing features in the latest version of our app. At 0:45 notice the difference between data captured by 13-bit variant (red) and by regular motion sensor tag with 8-bit temperature sensor (dark blue).

We are also transitioning to version 2.1 motion sensor tag firmware which provides hardware support for a new motion detection mode, in which they will transmit only at motion start and motion stop, i.e. when no motion is detected after a programmable timeout.)

No push notifications to iOS devices was sent from midnight-12:30PM today. This was due to server certificate expiring needing renewal. Now push to iOS device started to work again. 

We apologize for any inconvenience. 


We are putting KumoApp live today. If you used our iOS app, you may have wondered what the "Install KumoApps..." is for. The configuration interface for KumoApp has been implemented in the iOS app since last October.  "Kumo" (pronounced Koo-mo) means "cloud" in Japanese and "Kumostat" is our up-coming energy saving, Internet thermostat that will cost as little as the cheapest thermostat you can find (just like Wireless Sensor Tags is the cheapest Internet connected temperature sensor, thanks to our unique "Tag Manager" + "Cloud" architecture that moves hardware complexity to cloud where computing power is dirt-cheap). "Kumo-Sensors" are our high-end sensors with more accurate temperature and air humidity sensor + PIR or door/window designed to automate "Kumostat" to save energy and provide comfort. The adaptive, energy saving, and learning algorithms will all come from "KumoApp". 

While we are waiting to get the plastic casing for Kumostat and KumoSensors done (expect Q2 2014) so we can start shipping these new products, we are putting the KumoApp engine out for everyone with Wireless Sensor Tags to use. Currently, there is only 2 app (that does not require the Kumostat hardware) already written: "log every tag updates" and "log events from IFTTT". In the next few days, we will add more apps to show-case the capabilities of KumoApp engine, that will be useful even without Kumostat hardware.  You are welcome to write your own app today and test them out in your account. Show us your ideas and we will publish them for everyone to use. 


We are moving server to a larger capacity, faster server on Dec 22~23. During this time, and may not be available, and the iOS/android app may not function. When the down time starts, the database will first be shut down so that you can not make any changes to your setup while we copy everybody's setup to the new server.

After the server is back online (expected by 4PM PST on Dec 23), your tag manager may not automatically reconnect and need a power cycle (please unplug the power cable and plug in again). We apologize for this inconvenience. 


Effective immediately we are increasing the price for motion sensor tag from $19 to $21. The reasons are

  • Significant price increase in the elastomer (Dynaflex™ TPE) material used to make the sleeves and labor in producing them
  • Significant price increase in the 3D compass sensor chip
  • Price increase in the radio chip. 
  • Labor cost increase in PC board manufacturing and final assembly. 

We are planning to introduce a white Polycarbonate enclosure (just like that for the Tag Manager) for the motion and water sensor in near future, so that we can reduce the cost and keep offering this product at a stable price.