macOS version 2.5.1 and iPad version 2.3.2
Easily draw chemical formulas and reactions with MoleculeSketch
Atoms and bonds are nicely positioned by locking (can be disabled). The types of bonds can be changed by clicking on existing bonds. Different atom and bond attributes like missing hydrogen atoms, non bonding electron pairs on heteroatoms, font size and type, bond line width or color can accessed and change through popover panels.
Add reaction arrows and text fields. The average mass and formula of molecules can be calculated from the menu bar.
Copy/paste/cut molecules and drawings inside the drawing area or to other pdf compatible Programs.
Use trackpad gestures for zooming and rotation.