Blue nose

In the last two days Affinity Photo on my iPad has become so slow that brush strokes take seconds to show up. I restarted Photo and restarted the iPad but that did not solve the issue. I even cut down the file size by deleting layers and cropping, to only 8MB. Still slow. I don’t know how to reset the Photo app. Can anyone help?

Thanks, that would increase productivity.

How do I stop this annoying circle from appearing next to where I touch the screen while using the node tool? Also can I set the selection tolerance level to select only what my pencil is actually touching?