Sprimo Personal Air Monitor is a tiny accessory for iPhone users capable to measure the quality of air we breathe. This is a product of a Kickstarter project from Sprimo Labs back in April 2017. They promise Sprimo to be the world’s smallest air quality detector, and indeed I haven’t seen anything smaller than this.

I received this product around 2 weeks ago. It does come with a packaging box, but the product is not inside the box. Instead, they send me a packaging box in a flatten form, together with the sensor, in an envelope. I presume this was done to save on shipping cost. My first problem came a few seconds after opening the envelope. The sensor has sticky tape attached to it, and it left some really annoying residue when I peeled it off. Wasted good few minutes just to clean that off.

Connecting the sensor to an iPhone is easy, thanks to its built-in lightning connector. All I needed to do was downloading the app, plug the sensor and I’m connected. The sensor gets power from the lightning connector, so no battery is necessary.

According to the Kickstarter project page, this sensor is capable to detect temperature, humidity and the presence of various VOCs (volatile organic compounds) such as formaldehyde, acetone, alcohol, ethanol, ammonia and toluene.

The built-in lightning connector is handy. However, it is not compatible with almost all of my iPhone cases. The only case that’s compatible with this sensor is Apple’s official case, and it’s not the one I use everyday. So I had to change my case just for this experiment.

First display showed that the sensor needs time before it can show accurate reading. Apparently Sprimo Labs went extra mile to warn their customers about this with a piece of paper included in the envelope telling that it needs 5 minutes warm-up period. Okay, I got it, I needed to wait 5 minutes, so I did.

5 minutes later, I got calibrating display with reading value swinging from really high to really low. Again, this was also mentioned in the piece of paper that came with the product. They had warned us that it’s normal. So I waited.

And I waited.

And I waited.

Then I tried to bring the sensor to different rooms and locations in my house, as suggested by the app.

And I waited.

And I waited.

The calibration seemed to take forever.

And I got tired of waiting and decided to call it a day.

The next day, I tried again. Apparently the first 5 minutes warming up had to occur every time we plug it in, so I waited.

I tried different ways to expose the sensor to various extremes, so I put it near a kettle with hot water, and I put it in front of my fridge for several seconds.

This time, after 30+ minutes of moving around the house like a crazy person, I finally got the device to stop displaying any warm-up/calibration/adjusting message. The display finally showed a definite score for the air inside my house: 1.9, which is in red category, very unhealthy.

Wait, what???

I live in Melbourne, a very clean city, and I live in one of the Northern suburbs around some hills, so I’m confident that air quality should be at least slightly better than in the city. Maybe it’s my house that’s really unhealthy. So I brought it outside the house to the nearest park. It was such a fine day with really fresh air in the park and the reading from my sensor was… 1.7. Great, the park scored even lower than inside my house.

Next, I brought the sensor in my evening walk next to a busy road. It was still a fresh air, in my human interpretation, but should be at least a bit more polluted because of all the cars. The air quality score according to Sprimo was somewhere between 2.5 to 3.0. Okay, so major road with a lot of cars has better air quality than a park. Next I carried the sensor to a department store, it scored around 2.0 to 2.3.

Now the most interesting thing: after all the tiring experiment, I decided to stop at McDonald’s to get something. Inside the restaurant with air that noticeably feels stuffy compared to outside, my sensor shows air quality of… wait for it… 8.2.

Excellent. Let’s just live in the nearest McDonald’s restaurant then.

I lost all hope to trust this extremely-slow sensor.

Few days later, I decided to download the app in my unused iPad. Then I plugged in the sensor to the iPad all day long. I would occasionally unlocked the iPad to see how it goes. Most of the time, it showed that it’s either calibrating or adjusting when the app is opened. I quickly noticed that the score gradually gets better. In the first day, it still showed scores between 0.8 to 2.0 inside the house. I kept it attached for more than 36 hours before I had to recharge my iPad. Then I reattached the sensor for another 30ish hours and the score started to shift towards the range of 3.0 to 5.0. I repeated this cycle 2 more times, scoring at least 80 hours of connected time, and the score started showing numbers between 7.5 to 9.0.

Then, I updated the Sprimo app with a new version yesterday (14 Jun) and using this version 1.2 app, it shows score around 6.5 to 7.5 inside my house now. I haven’t had time to redo all my experiments once again using the new app. I honestly don’t know if I’m still willing to do those again.

One thing still does not change from the old app to the new version: from the moment we plug in the sensor to the time we can expect a meaningful reading, it would ALWAYS take us at least 15 minutes, most of the time it’s more than 30 minutes. Just by this trait, I fail to see the usefulness of this sensor. If the air quality in a place is hazardous, what is the use of a sensor that can only tell us that after 30 minutes? Meaning the user would have to stay there and breathe the air for 30 minutes?

From the scale of 10 (with 10 being a perfect product), I will give this product -3. The sensor works at least for temperature and humidity, but it’s practically useless to measure the real air quality. It takes way too long to get meaningful reading, and I couldn’t get myself to believe the reading even I finally get one. Remember that many times it confidently declared my clean house as hazardous area.