I had a very nice, somewhat huge, open reel-type 300-foot surveyor's tape measure that worked well until one day it wound funny and I spent a couple of fruitless hours trying to un-jam my $100 measuring investment. I also own an electronic (ultrasonic) tape measure... but that needs a big hard surface to bounce off and only works up to about 30 feet. Actually, you can buy conventional tape measures up to about 25 feet that can be stuffed into a largish pocket... but I want something closer to the size of a 6-foot tape measure. This device is honestly a bit awkward, but it can get the job done and is smaller than an Altoids tin .
I'm sure some readers are thinking "why not just measure what you can with a short tape measure, mark where you stopped, shift the tape measure to there and repeat until the destination, adding the measures to get the total distance?" Glad you asked. Two problems. First, out in the real world, it is hard to be accurate about starting the next measure exactly where the previous one stopped. Second, it is difficult to keep a straight line from start to destination, biasing the result toward overestimation. In summary, accuracy would be much poorer for long distances. Making a calibrated "tape extension" line solves these problems.