Pixelitor 4.0.2

Pixelitor is a Java/cross-platform image editor. It provides image filters, drawing tools, layered editing, bleding modes, multiple undo steps, etc. Its main attraction are the more than 80 unique image filters and color adjustment tools. Besides supporting standard graphic files, it defaults to saving in its custom PXC format (a gzipped Java object serialization for retaining layer data).

Oneshot 0.42

Oneshot is a very simple picture editor. It provides few features, but line drawing, adding arrows or circles, boxes and callouts to photograps. It's intended for unversed users; supports copying+pasting, or clipboard exchange however.

AprilBrush 0.2.0

AprilBrush is a digital painting application with support for layers and pages, different brushes, its GUI implemented with Qt5/QML/JavaScript. It uses the OpenRaster format for its image files, but can also export to PNG. AprilBrush is best used with a pressure sensitive input device (graphics tablet).