When Apple introduced iOS8 one of the features that perhaps didn't grab the headlines was that it allowed you to install third-party keyboard apps from other developers. Whilst the early examples seemed to do little more than change keyboard colour more recent ones have introduced novel features and discipline specific keys. There are three keyboards in the mobile science database.

Chemistry Keyboard The Chemistry Keyboard is a specialized Keyboard Extension for anyone who needs to enter chemical formulae. Allows you to add those nice superscript or subscript 2s. Or a proper arrow glyph, or a triple bond?

The Math Keyboard The Math Keyboard is the ideal keyboard for typing Math and Scientific characters.

SciKey - Scientific Keyboard SciKey is a Scientific Keyboard that brings you the essential scientific characters for your iPad, iPhone, and iPod touch. Now fully customizable, with more than 3,000 characters to choose from, to build your perfect keyboard (requires in-app purchase). It includes Greek and Latin letters, mathematical symbols, emoji and much more missing from the standard iOS keyboard. It also works for text snippets