The latest development version of Pocket Sudoku now contains support for the simplest form of Colour Solving, often referred to as "Simple Colours" or "Single's Chains". It is basically a chain strategy that lets you exclude candidates by looking at pairs of candidates. An easy to use GUI addition for Colour Solving still needs to be done, but as the solve/generate core now has support for it, that won't be long.

See the attached screenshots for two demonstrations.

Cheers,
Emil