Pollution sensors for indoor use that can be plug via USB to the mobile phone are really cheap, you can find laser ones like Nova SDS for $17 and some that are not so precise come even cheaper than that.
So unless the author buys a real PM2.5 sensor and does a test in a true room and not a box of the size of a Desktop PC, with the sensor on the opposite side of the room, and proves that the pollution drops to below 8micrograms/m3, in a reasonable time frame, than we can say that it is working.
Until than we can only say that the purifier is only able to purify a desktop PC.
So unless the author buys a real PM2.5 sensor and does a test in a true room and not a box of the size of a Desktop PC, with the sensor on the opposite side of the room, and proves that the pollution drops to below 8micrograms/m3, in a reasonable time frame, than we can say that it is working.
Until than we can only say that the purifier is only able to purify a desktop PC.