IMatch gives you several ways to open images in other applications.
You can use the Open command (<Ctrl>+<Shift>+<O>) from the Image menu or the context menu of the thumbnail window to open the selected image(s) with their associated applications. This command works the same way as a double-clicking or using the Open command in Windows Explorer.
Drag & Drop
Use the mouse to drag the images you want to open from the thumbnail window to the taskbar icon, desktop icon or window of the other application.
Choose an application from the Tools menu. The Tools menu gives you access to all applications which have been added as shortcuts to the UserTools folder in IMatch.
You can configure which applications are added to this launch pad via the Customize User Tools command in the same menu.