como mudar a resolução da imagem?

Hi Celina. 

You  can change the canvas size/resolution of an in-progress drawing by tapping the gear icon in the upper nav of that open drawing and tapping on the Size. That will launch a new format panel where size/resolution can be changed.

Please keep in mind... If you have been drawing with Pixel brushes on a small canvas and you increase the canvas size your work may pixellate.

Let me know if you have any trouble.

Sue.