For full disclosure this product was provided for free by Ink-Bird for us to review. Also they are a sponsor of www.smokingmeatforums.com. Review of Inkbird IBT-4XS Bluetooth Wireless Digital Thermometer When I received this unit I noticed it’s nice and compact. Packaging was simple and clean. From the time I opened the box to putting it into the smoker was no more than 10 minutes and that was with some tinkering with the unit. Bluetooth connection to less than 60 seconds to get the app to link to the unit. It worked on the first time and without any issues. I used a vertical pellet smoker for the test. The controller attached to the side of it nicely. The controller is rated up to 176F degrees for the casing. The pellet smoker has an insulated wall so it never gets above 120F degrees. If you are unsure of what your surface temperature then I would recommend an IR Laser Thermometer for checking before using. The thermometer connections are a little tight and required some force to insert. This isn’t a bad thing as it will stay put and be nice and tight. The probes that are provided are average units from what I have seen. If you want some heavier duty ones I am sure you can get them. The read time on the probes was quick. Appears to be reading every second. When I put 1 in the Turkey and 1 in the Smoker the turkey came to temp in 30 seconds. The chamber probe took 2 minutes to level out. The Bluetooth works really well. I turned off my Bluetooth to drop the connection to test reconnecting. When I turned it on the unit reconnected in about 10 seconds. The app was very easy to use and very simple. A few things I noticed is that when viewing the graph the temperature numbers it shows on the left side go 70, 141, 212, etc. It was odd not to have it in 5 or 10° increments. Also you cannot zoom in on the graph to see it better. Another down side to the app is if you lose Bluetooth connection you lose all graph data. Also there is no way to save prior sessions on it for future reference. It did have alarms that are very customizable but you are not able to name each channel. The channel will only show the name of the alarm you set. So if you want one labeled pit then just create an alarm and name it pit. The app also shows battery level and Bluetooth signal strength. The alarm on the app will definitely get your attention which is very good. In the first 2 images you can see on the left it’s the home screen. If you click on the diagonal up arrow on the upper right you it will take you to the graph screen which is the second image on the top. Here it will graph your temperature for you. The third image shows all of the preset’s they come with for you to use as alarms. You do have the ability to set your own custom alarms and the forth picture shows your options for a custom alarm. After I was done with the Turkey I decided to let it stay in the smoker and let it go until the battery died to get an idea of run time. It lasted about 53 hours. The unit only takes about 2 hours to fully charge. I did notice that the unit reported inaccurate % when the outside temperature got too low. I was in the 20F’s overnight. When I woke up on day 2 and looked the app say battery level was at 1%. I turned the smoker back on and the controller warmed up and the battery level now showed 17%. I know this can happen when a battery is in a cold environment. This is the exact reason car batteries have a cold crank amp rating in addition to the normal ratings. The instruction manual states you cannot use the unit while charging. I tested this and it does work while charging but the battery level says 0%. I am not sure why the manufacture states there but I am sure there is a reason so I would not recommend doing something outside of what they recommend. The downside to this is if you go to use it and its dead you have to wait for it to charge before deploying. The last thing that I did was a boil test to check accuracy. I used 2 other units that I have that are really reliable and 1 came with a certificate of calibration. Both of the control thermometers read 203.7°F. Note I am around 5000’ elevation so this is about spot on for boiling temp. The Ink-Bird was reading 205-206°F on 2 probes. So about 3 degrees different which isn’t bad. But when I tested in the smoker my control unit was reading at 250-260°F and the Ink-Bird was reading 280-290°F. The probes were 1” apart from each other so I am not sure why there was such a difference. Taking into consideration my first temperature test I decided to run another on this time inside of a convection oven. I used 2 control units with new probes for each one. For the Ink-Bird I used 2 of the probes. On the control units the temperature maxed out at 446.7°F degrees on 1 and 447.7°F degrees on the other. The Ink-bird probe#1 maxed out at 462°F degrees and probe#2 455°F degrees. So between the 2 probes there was a 9-16°F difference. This is a lot better than the 30°F I initially saw in the smoker. Still not sure what cause the big difference in the smoker but am glad that it leveled out to a manageable level. In conclusion I like this unit. For the price point $54.99 for the unit and 4 probes or for $39.99 you can get the unit and only 2 probes. I do not think you can go wrong. If you are looking for a unit with more features you can find them but not for the price point. You can find it on amazon and here is the link https://amzn.to/2DCThbG Thru 11/20/18 20% off discount code: VX687DL4 Initial impression · Nice and Compact. Simple packaging and instructions. What was included? · 1x Control unit · 2x Grate Clips · 4x Temperature Probe · 1x Micro B-USB Cable Battery · 1000mah rechargeable lithium battery. · Advertised at approx. 60hrs run time. Achieved 53hrs during testing. Features · Magnetic Back to mount unit to the smoker/oven (up to 176F surface temp) · Monitor 4 channels at once Accuracy · +3F degrees at boiling Connectivity: Wifi:No Bluetooth:Yes · Advertised at 150’+. Open line of sight I was able to get 142’ and obstructed line of sight 80’-90’. Temp Range · Controller: 32F – 572F · Probe: 30F-482F App · Simple and user friendly Pro’s · Easy setup. · Quick charging and long battery life · 4 probes at once · Magnetic back Con’s · Can’t use it while charging per the instructions. · App is a very simple. · Can’t track sessions. · If Bluetooth loses connection you lose graph data. · Only reads down to 32F degrees. · Battery is not replaceable. Overall Overall this isn’t a bad unit. It would work well in your smoker, smoke house, or even in your oven. As with all thermometers make sure you do the boil test and know what the boiling temperature is at your altitude. This will ensure that you know what temperature you are working with. Because of its no frills approach and good price point I’d have to give it a 7 out of 10 rating or 3.5 out of 5 stars. If you have this unit click here to go to the review section and leave your thoughts and opinions.