the application optipng-ui has been discontinued
The OptiPNG-UI application, that is the graphic interface I made in 2009 for the OptiPNG program created by Cosmin Truta (Canada), is no longer available.
A new project, named PNG ToolKit, completely replaces the previous application and contains many new functionalities; since this is not a simple update of the previous version, but a completely redesigned software, I've also decided to change the name to match it to the new contents.
I thank the over 20,000 users who downloaded OptiPNG-UI since 2009 to 2016, from more than 100 different countries.
If you want to continue to optimize your PNG images for free, you can use the Free version of PNG ToolKit.
If you want to find out all the useful tools provided by PNG ToolKit Professional you just have to try it for free.
PNG ToolKit makes PNG image optimization using the latest available version of OptiPNG (vers. 0.7.6), application created by Cosmin Truta.