As a fabricator of 40+ years, the last 30 or so as the workshop manager, I have constantly used trigonometry etc. To calculate cones, segmental bends and much more. Nowadays I am constantly asked by the fabricators to calculate developed lengths etc. To save them the time and effort of laying it out.
You can get the setup package of Segmental Bend Developer Oct 19 free of charge and have a look at users' reviews on Droid Informer. The app works fine on Android 2.1 and higher. The download of this application doesn't contain viruses or any kind of malware. Segmental Bend Developer has been originally designed by Gellis apps and it refers to the Tools category.
The most recent update of the app was launched on Sep 3, 2020 and this application has been set up by over 0,5K users. People rated Segmental Bend Developer 4.4 on Google Play.