I have the inside/outside temp sensors, the rain gauge and the wind gauge working, it was a struggle. The instructions they send along are near worthless. The procedure is what I used to pair the equipment to the main weather station. 1. Weather station: Goto weather station setup under install new equipment, Press start, plug in unit, touch top of unit so light comes on on station, this causes unit ti send out pairing signal, press next, answer yes to question. Select wi-fi and press confirm, select home name. 2. Select add-ons: outside weather station, press start remove battery if installed wait 1 min. press next reinstall battery this causes pairing signal to be generated , place outside station next to inside weather station they should pair. wait if nothing happens after 5 min repeat procedure. Repeat the same procedure for Rain Gauge and Wind Gauge, always press next before putting in the batteries, this causes the units to pair. The units appear to be accurate enough for casual use, I have a question about batterie life. Patients are required great patients.I've had this PWS for about 3 months now. For a while the outdoor temperature readings have been 2-6 degrees off whenever it got cold in my area (also hot too). All other readings seemed okay. After a bunch of experimenting over weeks I think I finally have been able to get accurate outside temp readings without even applying any calibration offset in the iOS app. In fact that offset isn't very good because if your temp is off, it will be off in a non-linear fashion with changing temps, so applying a hard offset won't really help.The outside module is so convenient to just place on top of a table or any hard surface without trying to mount it on an arm. Initially I had it placed on the edge of a patio to try to get it as close outside as I could but also keeping it away from sun and rain. But that gave incorrect readings. I think the issue is that whenever you have the module anywhere close to the home structure there must be some non-negligible heat radiation coming off the structure to influence the module significantly. I moved the module to the outer edge of my pool cage on a waist-high railing, which put it about 20 feet from the main house structure and now temp readings day and night are definitely in good agreement with surrounding stations and airport, maybe a 1 or 2 degree difference among some surrounding stations (looking at wunderground's map). Also, since its not mounted on an arm, I found placing it upside down so that the vent holes are not close to the surface it sits on helps too. There is also temperature influence with what it sits on.The only other main challenge now with its new position is ensuring sunlight never hits it directly. I think I have that resolved but its definitely something you will have to consider if you move it away from say a protective patio of your house. Also, while folks claim that the module should not be exposed to rain - I do not see that mentioned in the manual, only that it should not be in sunlight since it will absorb heat and throw off the temp reading. There are companies that sell solar radiation shields for PWS use as well, so that is always an option. I think Netatmo should sell that as an add-on.Hope these little findings of mine helps anyone that may have similar troubles. I must say that when I look at the wunderground map I see some station reporting temps that are outside the consensus of stations around it. I look at the hardware being used and it's been about 8/8 being a Netatmo PWS! This means that it is fairly common for folks not taking great care in the placement of the outdoor module but I don't really blame them, the documentation is severely lacking. The hardware is fine, I wish Netatmo would have basically provided the information I mentioned in this review in the manual. I had to figure it out myself over time. It is almost as if they don't really know their hardware very well because I have read some of the reviews on here reporting issues with the module and the suggestions given from Netatmo were a bit crazy. Have to dock a star for that.I love using Netatmo despite the documentation/tech support issue however. I've given new life to old iPhones and iPads being mounted weather info screens around the house. There is an SDK for those who are interested in having custom software interface with the hardware. My next task is to have some code which will acquire rain totals and use that to configure a sprinkler controller that is also internet connected. One practical use of having a PWS that is internet/intranet capable. If you are on the fence about buying this PWS I'd say to go ahead and get it once you give some thought to where you will position the outdoor module.I am writing this review in response to an email request from Netatmo.1) set up of the main unit was easy and problem free. Simply plug the provided USB cable into your computer, download the Netatmo setup software and in minutes it worked.2) setting up the outdoor unit was just as easy.3) the Netatmo app (I have only had experience with the IOS version) works as promised. It seems to be pretty much bug free.4) My network has been up and down a lot (thanks AT&T) since this Netatmo arrived and it has had zero issues reconnecting to the network unaided by me. Robust would be a good adjective for this aspect of the Netatmo.5) Purchased an additional add on indoor module. After several days of trying it simply would not recalibrate the CO2 levels. So rather than being frustrated I just boxed it up and sent in a return and replace request to Amazon. After the replacement arrives I'll post how it does.6) If there is anything I can't stand is a company with poor customer support. I was sad to read some of the other reviews that mentioned how poor Netatmo's customer support is. That is why I chose to just return the product. Why be frustrated when a costless (though a bit of a hassle) alternative is available.A message to NETATMO: If you want to grow you must have excellent customer support. Fix this problem.FOLLOW UP INFORMATION:THE GOOD: I received the second/replacement indoor module. Connection was easy and it calibrated the CO2 levels quickly, unlike the first unit I received. I have been comparing all the Netatmo units against some rather fancy thermometers I brought home from my laboratory. The Netatmo units track the lab thermometers within a degree or two which is acceptable. The Netatmo humidity readings are relatively accurate also when compared to the two mechanical hygrometers in my home. The CO2 levels are showing what would be normal in a home with good fresh air circulation, which my home has, so that is good too.THE BAD: During the setup I found that a "ghost" indoor module unit is showing up in the Netatmo Module Manager software. Thinking that this may be a problem I emailed Netatmo Customer Support (no phone number) to enquire about what to do to resolve this issue as there doesn't seem to be any documentation or facility within the software itself on how to handle the issue. This issue is not causing problems but I don't know what hassles it may conjure up in the future so I would prefer to have things properly (in my opinion) set up. The email was sent two days ago and I have not received an acknowledgement of receipt or response from Netatmo. Perhaps I just don't exist.AMANDA, if you read this I don't want a post from you here at Amazon, rather, I would like a reply to my email.CONCLUSION: In my experience the product (all three Netatmo stations) are functioning as advertised. I am happy about that.Netatmo needs to fix their customer service issues and, in my opinion, really should personally contact all those they have ignored. This product would get 5 stars if I had heard anything from Netatmo regarding my customer service request.Bought this to replace a 15 year old weather station that died. Online tech reviews are great for this and convinced me to buy. Setup: I have a timed-access/MAC address protected network where you have to add the device's MAC address to the router to gain access. I couldn't get this device to give me its MAC address at all, it will only follow the app for setup. I turned off my router's timed-access just long enough for this to setup, and then I could get the MAC address from the app to add to the router... other than that little extra bit, setup was a breeze. One of my favorite features is getting to see other people's Netatmo stations... there's one near my office so I can see conditions outside my house as well as what it's like at the office in real-time. Since I bike to work, that's a great feature for me. The CO2 and noise level notifications are pretty nifty too. Overall this has been a really cool gadget and I'm very happy with my purchase.I was so much hoping that this would work! Unfortunately, it didn't. The humidity sensors of both the indoor and outdoor modules were so far off all other measuring devices I have (4 of them) that Netatmo support agreed to "recalibrate" them. But it's not a real calibration. They just add or subtract a fixed number of percentage points which means it only "fixes" linear error and, in my case, it meant that it would never go above 90% relative humidity (because they subtracted 10 percentage points from what the device was saying) which just made this an expensive piece of junk which I returned for a full refund.I wish I could say something different, but this product is simply not ready for the market. I don't understand how they can still sell this. I'm thinking that maybe their quality control is just not working so that I (and many others) received bad units? But in that case I'd expect the support to offer me another unit for free, but they never did. So I guess their business model is just that most people have no other meters to compare to or just don't care about accuracy...No sirve. Solo funciona el módulo interior. El exterior marca que está muy retirado a pesar de estar colocado en una terraza a 3 m. del principal. Imposible emparejar el pluviómetro. El anamómetro siempre marca la misma dirección.The readings from either the indoor or outdoor module were so far off from reality I wondered how such product ever made it to market. My main interest in this station was to be able to remotely read humidity in the rooms in which I store my expensive guitars. Anything else would have been a bonus.After initial setup, I noted that the humidity of the indoor modules was at 56% while the outdoor module read 51%. I used 3 very accurate **humidity gauges to compare. Each of these read the humidity to be at 44%. I requested that NetATMo support re-calibrate these modules and, after 72 hours, they did just that. Reading now were 47% for indoor, 45% for outdoor, 42% for the 3 other gauges. I moved all gauges to a known dry area (33-35%) and noted the following:Indoor: 42% (it seemed stuck at that reading)Outdoor: 39%3 other: 34-35%I requested another re-calibration and withing 24 hours this was completed. Things started to look up. All reading were very close to each other (35-37%). Such slight variation was not an issue for me.I then placed all gauges in a room with a know RH of 40%. All gauges except the indoor module read 40-41%. The indoor module didnt go any highers than 37% even after 2 hours in the same room.Next, I placed all units in a room with an average RH of 49-53% (has a humidifier hence the 4% fluctuation). Results:3 gauges - 49-53% .dead on each timeOutdoor - Never got higher than 47%. Dropped down to 46% as RH dropped as indicated by the 3 gauges.Indoor - Never got higher than 41% in the entire time in this environmentThis product can not be relied on and I have returned it for a refund.** Caliber IV by Western HumidorReading a lot of possitive reviews about this product, I am settled with one to join the happy boat!No complaint so far.Only suggestion if I may, someone please come up with a way to view these info this devices offer to a physical screen?