Looka - Make a logo you’ll love with Looka Logo Maker.
Sketch Mirror - Preview your iOS designs directly on your devices
Logo Dust - Free logo designs for your projects, added every week
Flowkit - Sketch library for user flows/content maps/annotations
Canva Logo Maker - Create your own custom logos without having to hire a designer with Canva's impressively easy to use logo maker. Completely free, completely online.
Artrage - A simple but lovely natural media painting and sketching program.