Jolly Logic AltimeterOne

Works great. Easy menu to work with.

Works like it should. Small and light weight, perfect for smal to large rockets. The signal button can be a little confusing until you get the hand of clicking versus a long press. Pro tip: tie a bright streamer directly to this in case your shock cord breaks. You will have better chance of recovering it.

Works as advertised

Works as mentioned in description and directions. Used for my son's science experiment to measure rocket altitude.

Unfortunately it has only 1 work mode that provides RELATIVE altitude to a point that you select to be zero, so I had to keep it on all the times to see absolute altitude at all times, and had to do zero - ing at a hight that was already known and back calculate everything, its a shame that it has only relative measurement mode. Otherwise it is top quality solid small long lasting

I use the this Altimeter One on my Water Rocket STEAM Project to track the altitude of their project when launched. However, the altimeter is very fragile. At the 5th grade level most rockets only achieve an altitude of 50m; although there are a few students who do a well enough job that their rocket may get 90-100m. After 3 launches under those conditions, the casing of the Altimeter One cracked. I fixed it and used good ol duct tape to reinforce plastic housing unit at the seams, 2 launches later the plastic housing was fine but LCD display turned black. I let it sit for a few min and it began to work again; however, it only worked intermittently for the remainder of the student projects. I Started to use it again this year a few weeks ago, with my new class for the same project, and after only 3 launches it was done. I couldn't even get it to turn on. I liked the product enough, not give up on it so I have just ordered a replacement and upgraded to Jolly Logic Altimeter Two. I am hoping that the case will be stronger and the overall device will be more durable.

Wow Wow Wow This thing is incredible, We used it to survey a water system for a remote village in a third world country and took measurements over about 3 kilometers with height differences of 205 mtrs (not feet) in total. We rechecked the measurements in reverse on another day and they were accurate to within a foot. I spent a lot of time trying to find something to do this job, it is outstanding. Take measurements quickly before the weather changes or what is best just reset at every way point (DO NOT TRUST A GPS) we found this out the hard way. Every person who is doing these sort of projects MUST have one of these.

I bought this to use for a junior high science class I teach. My students were tasked with building a water bottle rocket of their own design with the goal of launching the rocket as high as possible. Unfortunately, this did not record the height of their rocket launches. I followed the instructions to set the altimeter and attempted to record heights on at least 5 launches with no luck. Also, this altimeter cannot handle ANY moisture. The field we launched the rockets in had a layer of dew that got the altimeter slightly wet. After only a few launches, the water seemed to get into the display, making it practically unreadable. I would have tried to initiate a return, but being a teacher these things tend to slip your mind.

I needed an altimeter for my powered paraglider. I used to use my iphone but didn't like the display. In real-time mode this shows me a constant display of my altitude based on ground level where I took off. It seems to be very accurate and is based on barometric pressure. The only con is that the display is quite tiny, but that doesn't affect me as I keep mine over my reserve parachute at chest level. Considering that this is primarily designed for model rocketry, I am very pleased with it and would not hesitate recommending it to my flying buddies.