Mari is a professional 3D painting and texturing software developed by foundery.com (the same developers as famous software like Nuke and Flix).
Ranked in these QuestionsQuestion Ranking
Pro Free Trial
Though it is expensive, if you wish to use it continuously you can constantly renew your trial with lovely fake emails. Learning this can benefit your career into games or film.
Pro FIlm Industry Usage
Though Substance Painter is catching up to Mari in terms of texturing wiht higher res textures, this program is what is used in tandem with Zbrush most commonly in Film. For the Game industry it is Substance Painter and Zbrush.
Pro Great at handling large texture sets
Mari can handle 32K textures since 2010. It was used in creating the characters faces and such in the Avatar movie, as close-ups require such high-res textures.
Con The most expensive one yet
Not made for hobbyists or indie game developers.