Affinity is offering 50% off their Affinity Photo Editing Software for Mac or PC ($24.99) for a limited time. They also have Affinity Photo for the iPad in the iOS App Store for $9.99 (regularly $19.99) for a limited time.
B&H Photo also has the Affinity Photo for Mac or PC for $24.99 for a limited time.
Affinity Photo redefines the boundaries for professional photo editing software on Desktop and Tablet. With a meticulous focus on workflow, it offers sophisticated tools for enhancing, editing and retouching your images in an incredibly intuitive interface with all the power and performance you need.