IN WHICH Fingers Paint while Dry, and Egos are Lightly Battered in a Hollandaise Sauce On Mixel Mixel confounds me as a piece of software that shines so brightly, the shadows of its flaws are made proportionately more apparent. Mixel is an iPad app for making collages that has the whole “social networking” thing baked into its DNA. Making a collage feels like something the iPad was born to do.