When software starts the default size is set to 64 px. On main screen there are also 64 checker blocks. Even if I change size the checker blocks have same size. I have to zoom out to decrease size of checker blocks.
The behavior of the transparent checkerboard was changed in v0.7 to be similar to other drawing apps. This way, jitter and dizzyness is reduced, which was especially noticeable in large images. Related GitHub issue: https://github.com/Orama-Interactive/Pixelorama/issues/208
You can enable the grid to help you with pixel-precision instead.