Toolbar (from left to right) – note the toolbar may minimise if your mouse is not over the map
<< or >> minimise or maximise the toolbar
slider bar – zoom in or out
4 arrows – move round the map (you can also click-drag on PC or drag on ipad)
circle with arrow pointing to top left- return to original view (from zoomed state)
square with arrow pointing to top right – go to full screen – recommended way to view
Fullscreen (on PC)
Mousewheel to zoom in or out or click to zoom in, ctrl to zoom out. Alt-click to zoom in 100%. Click-drag to pan. Esc to leave fullscreen.
Fullscreen (on ipad)
The usual finger “pinch” and “expand” actions don’t work. Use tap to zoom in and double-tap to zoom out. Drag to move around. To exit fullscreen use the last but one bottom on the toolbar shown as a square with arrow pointing bottom left.