Traditionally if I want to measure something, I need to go to the object and use a tape measure to take its dimensions. But what started as a project in the survey world, eventually moved to the logistics world and law enforcement.
If I take a photograph of a house (for example) in the distance, I have a fixed representation of an object made up of many pixels. If I combine a laser with that camera, then I can measure the distance to the house and now I can scale the image. I can therefore calculate the height of the house, or the size of the windows etc. The accuracy is really down to the quality of the image.
The small laser was created to provide an add on to a PDA or mobile phone so that it could be used as a survey tool. Suitable software could measure objects with this combined system to prevent somebody physically visiting the object. A side line to this is that when you have GPS built into your device, you stamp the picture of the house with the coordinates of where you are standing. If you have a laser distance too, you can calculate the GPS coordinates of the house in the picture (need a compass for direction too).
Whilst looking for partners for this development, two more applications were identified. One with Royal Mail in UK to take a picture of a parcel being collected and hence calculate the dimensions of it, for quick measurements of volumetric weight. Again another consequence of the same hardware with a laser, meant that the GPS coordinates of the correct delivery point of a building could be identified. Stand away from the delivery door, aim the laser and with coordinates of where you are standing and the offset, the coordinates of the drop off (or collection point) were identified for future drivers.
The second spin off application for the device was a digital camera with laser mounted on the bottom. It could be used for all of the above, but in addition a well known camera manufacturer wanted to add the ability to record speed of vehicles too. By making multiple distance measurements, you could calculate speed whilst recording the image.
Again using the small laser and a mobile phone, all of these applications could be performed. Back in 2010, this was an extremely novel addition and still has potential over 10 years later