The first and most important element of ODOP is it is open source, on GitHub you can see all the work being done on the program and contribute if you have the ability. The second best feature of ODOP is it is entirely free, At the time of writing this I would say there are programs better than ODOP but one example I can think of is $1250 a year... Unlike other free spring design programs ODOP actually delivers most of the functionality of the excessively expensive programs without any of the cost. ODOP is still in development so I expect it will surpass most if not all the other spring design programs many of which do not receive updates anymore.

ODOP can be a little difficult to figure out at first, not everything is entirely straight forward and it is still in development so it is missing a few features that will likely come in the future.

If you're only working standard compression, extension, or torsional spring, ODOP spring is a good option for designing a spring. If you only need the software for few spring design requirements a year, its especially hard to justify buying or renewing a license for any expensive commercially sold software.

I liked how the software would allow the constraint of specific variables, and the other variables could change in the analysis section of the software. Hence, your initial parameters were slow tweaked until you spring meet the requirements for spring life and force requirements. Upon completing a spring design, the results were compared to calculated results using standard spring formulas, and the software was spot on. We also compared to the results to another commercially sold spring design software, and we got similar results.

I wish the software included a list of standard wire sizes with material properties, so you could adjust your design to match a standard wire size. If your spring is cost sensitive, you need to stick to standard wire sizes. When compared to other commercially sold software, the ODOP only allowed for three types of spring, and the Spring Manufacturers Institute software offered the most.