ChemDraw - ChemDraw - The Gold Standard for Chemical Structure Drawing and Research Publications.
Sketch Mirror - Preview your iOS designs directly on your devices
Avogadro - Avogadro is a free, fantastically easy to use molecule editor.
Flowkit - Sketch library for user flows/content maps/annotations
Gnome Chemistry Utils - The Gnome Chemistry Utils include six chemistry related programs:
Crystal: Sketch Mirror for Android - Crystal: Sketch Mirror for Android is an application that is designed for viewing your sketch designs in real-time, navigate prototypes and download content related to the sketches for offline viewing.