Handgun Hero was built after constantly searching Google Images for things like "Glock 17 vs Glock 19" or "Ruger GP100 vs SP101 size comparison" and not seeing useful side-by-side comparison charts.
Whenever a new handgun was released or a youtube personality made a video about a handgun, I would search online for images or charts to get a feel for it's size compared to models I'm familiar with.
After a lot of searching but not finding, I realized this was something I could build for myself as well as firearm enthusiasts. So here you go - I hope you find it useful. Please let me know if you have any comments or suggestions.