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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. 


When you configure "Auto-Update" for a tag, the server will send a command to the tag to configure it to send periodic status update (with temperature etc) at specified interval. An "out of range" notification is sent when the server does not receive periodic status update from a tag at expected time + some margin.

Because the tag stores the interval configuration in its local volatile memory, if you remove the battery and reinsert it, the tag will forget about the periodic status update it is supposed to send. As a result, soon you will receive a false "out-of-range" notification even though the tag is well within range. When you "ping" the tag, it will come back in range right after. 

When the tag tries to transmit status update the transmission fails for some reason, it thinks it is out of range and will enter into a "hibernate" mode, where it no longer sends any status update until receiving a new command from the Tag Manager. If the status update fails for enough number of times to make the tag enter hibernate mode, and then recovers afterwards, the tag does not know about it and soon you will receive a false "out-of-range" message. 

We have made a simple yet effective change to the server-side algorithm to reduce these false out-of-range notifications: Just before the server is about to mark the tag "out-of-range", it automatically attempts to re-configure the tag's "Auto-Update" interval, and only marks the tag out of range when this fails. Now when you receive "out-of-range" notification you know with more certainty that the tag is really out of range. Because this change is done on the server side, no app date / firmware update is needed. 


a false "out of range" notification a false "out of range" notification "out-of-range"

We discovered a bug introduced by a firmware update in Long Range Motion Tag on September 15.

This can be reproduced by the following steps:

  1. Set auto-ping/auto-update to some value e.g. 30 seconds.
  2. Unplug tag manager power. 
  3. At scheduled time (e.g. after 30 seconds), the tag transmits and retries a few times.
  4. Re-plug in tag manager, the tag succeeds in transmitting update.
  5. After a while, the tag will flash several times and then becomes unresponsive until battery is taken out and re-inserted.

If tag manager is kept plugged in, if the tag ever has to re-transmit due to temporary interference, this problem may appear. As a result, the system will appear very unreliable, as any re-transmission will trigger this bug. 

This problem only affects Motion Sensor Tags that were shipped between September 15 and 26 2013. If you can reproduce this problem, Please send an email to, we will send you a prepaid return shipping label for you to return the tags for firmware update.


For long range sensor tags, if auto-update interval is set to be 5 minutes or longer, you may receive false out-of-range notifications followed by re-established link notification. This problem is caused by each tag sending updates at an longer interval of about 1.5x the configured interval. We have fixed this problem from the server side. To apply the fix to your set up, please from Web App, click Settings->Wireless... and change to some different frequency, and click Migrate. For tags that did not respond, a yellow "Migrate Settings" button will show up, click it to retry migration.  We apologize for the inconvenience.



In new installation of iOS app (v1.8) the push notification does not register. This issue has just been discovered and has been fixed in v1.9 App. The v1.9 App also provides other bug fixes and cleaner UI, and new features below.

  • Reordering tag. Click gear icon and choose reorder. The tags will appear in the same order on all devices. 
  • User Interface for future product prototypes that are still not in production. Please ignore these until supporting products are officially released.
    • Contact based door/window sensors
    • PIR sensors
    • Thermostats (Kumostats)
    • KumoApps (People's algorithms that runs on the Cloud to schedule & automate interaction among sensors and Kumostats. Compose and submit using KumoApp Coder ).



For those of you who tried out our beta version motion sensor tags, problems below were discovered thanks to your feedback, and were corrected in the release version:

  • After beep function is used, unless the beep duration was less than 3 seconds (beep until moved), the tag requires "reset state" to function properly afterwards. This issue was due to a simple bug and has been completely fixed in the release version. To avoid this issue in beta tag, don't use beep function, or always "reset state" after beep.
  • Searching new tag sometimes cannot find long range tag. When tag manager is searching an unassociated tag, it cannot use wireless parameters optimized for long range tag or it will not be able to find old version tags. To keep user interface simple (no separate button to search for long range tag,) a special wireless setting is used in the long range tag until it is associated. The issue has been corrected by optimizing this special wireless setting.  
  • Association sometimes fails and requires a retry. This was because the tag manager was not using the correct setting. This has been corrected from the server side. We tested search, association and un-association for 20+ times in succession without a single failure that would have required a retry.
  • Perceived short battery life. This can be improved by enabling low power receive mode. We added algorithms in the server to enable this automatically if the server determines the tag is well within range and does not need frequency calibration.
    Because the tag draws battery current in short pulses of few mSec, the battery voltage vs. time graph resembles the last plot "Pulse Discharge Characteristics" of As this plot shows, the battery starts from 3.2V, but quickly drops to 2.8V after only ~10% of its juice is gone, then it stays at 2.8V for ~75% of its lifetime. Since the battery percentage is calculated proportionally from the battery voltage, you will see the battery percentage drops very fast from 100% (3.2V) to ~60% (2.8V), then stays at 60% for a long time. This sometimes give people false impression of short battery life after seeing the battery percentage drops so fast initially.

Since Wireless Sensor Tags were released 1 year ago, they have been tried out by thousands of customers, many of whom have provided us with valuable feedback, bug reports and requests for new features and improvements. During the first few months of the release, we were updating the software almost daily to fix bugs and adding those improvements. 

However, one common issue that persisted is sporadic "loss of link" which is caused by the limited range and reliability of the wireless connection. People also noted that the sensor tag range reduced significantly when placed inside metal fridge or behind metal door. We then realized that the final hurdle to our initial goal, a product with lasting value, was to improve the wireless performance. 

We spent the last eight months not on ads or marketing, but on listening to our existing customers and building the best performing wireless platform possible for our application. Wireless Sensor Tags only need to send a few bytes once a while, while WLAN or Bluetooth are used to send megabytes of videos or voice, so they are clearly not efficient for our applications. Meanwhile new "narrow band radio" chips are emerging for applications such as wireless meter reading. They are able to reach kilometers range by using very low data rate and receiver bandwidth, using expensive frequency reference (crystals) and big antennas (and with radio operator license). Utilizing these new wireless technologies, we developed a solution using less expensive crystals and same antennas to keep the same form factor to achieve 4x improvement in the range. 

We did this by a combination of increasing output power to FCC limit, using optimal frequency modulation index, better crystal and new frequency control techniques to allow 7x narrower receiver bandwidth to filter noise. Completely new radio IC with better noise figure and rewritten firmware are used in each tag and tag manager. We completed FCC part 15.231a certification for both the tags and tag managers.

Taking advantage of the much improved range, we implemented features to trade-off range with battery life, because not every application requires such a long range.

  • The new radio IC we used contains a neat feature to turn off receiver immediately after it determines radio power within the narrow channel bandwidth to be no stronger than the background noise it estimated over the last few cycles. We fine tuned parameters to make this work perfectly on each Wireless Tags. The result is 1/4 of the receiver on duty cycle in stand-by (vs. the old sensor tags and with the mode disabled) and hence ~4x longer battery life (not considering power consumption of sensors like angle based motion).
  • We implemented transmit power control in each tag, i.e. the tag manager automatically send out command to each tag based on received signal strength, so that each tag uses just enough transmit power to reliably reach tag manager. This means if the tag is installed in a location close to the tag manager, its battery will last proportionally longer.

All these performance improvement and new features come at only $1 increase in cost to you. This covers the increased components for a new front-end filter, higher price of the new radio IC and a better crystal. 


We have added a new feature in Web/Android app to display temperature, moisture, or battery voltage history for multiple tags on the same screen. Access this feature from "Stats..." button at the bottom of the page. 

Meanwhile, we have re-tuned the database that stores these log data and added more indexes to significantly reduce the loading time for the statistics page.


We have started shipping Ethernet Tag Manager with new hardware on May 6. Those who received shipment notice on May 6 or later had initial problem of not being able to associate a tag until today (May 13). This problem was caused by a lack of web server support of a last minute firmware update made to the new Ethernet Tag Manager. We have just address this issue by adding the web server support. If you have experienced this issue, please try again and your problem should go away. Our apologies for any inconvenience this problem have caused. If you still have problem, please send email to We will reply to your email within 2~3 days. Our phone support will be back on May 30. 


The latest iOS app (version 1.7.2) and web interface ( now support low battery alarm feature. When configured for a tag (all types of tags are supported), user can receive email, tweet and/or push notifications when its battery voltage drops below the configured threshold. The notification can be configured to repeat per hour, per day or per week until the battery voltage goes above the threshold. 


From about 1 week ago, the cloud server that passes user commands to Tag Managers had experienced performance issue. During that time, motion event/temperature information upload from tag to the cloud server (via Tag Managers) was not affected, however, user who tried to beep, arm or disarm tags may have experienced very slow response and server timeout error. 

This was due to an change we made to server configuration (locally run our "user command" forwarding server that used to run on a separate Linux server on the same Windows web server) intended to reduce service down-time, but turns out the Windows port of the server software originally written for UNIX caused performance problems. 

We have recently restored the old server configuration and have confirmed that these issues are now resolved. We apologize for any inconvenience these issues have caused.