An addition that I’ve been meaning to implement for awhile: double-tapping on an atom within the structure sketcher, using apps such as the Mobile Molecular DataSheet, MolPrime and others, brings up a periodic table and several sliders that allow atom-specific properties to be edited. Using a slider to edit the charge has always been a little unsatisfactory, so as you can see on the snapshot to the right, there are now 7 additional buttons cradled in the deadzone of the periodic table for quickly setting the charge from -3 through +3.

The modified sketcher feature will appear one app at a time, as they get updated during the natural course of events.