  Droplet condensation on surfaces produces patterns, called breath figures.
Their evolution into self-similar structures is a classical example of
self-organization. It is described by a scaling theory with scaling functions
whose universality has recently been challenged by numerical work. Here, we
provide a thorough experimental testing, where we inspect substrates with
vastly different chemical properties, stiffness, and condensation rates. We
critically survey the size distributions, and the related time-asymptotic
scaling of droplet number and surface coverage. In the time-asymptotic regime
they admit a data collapse: the data for all substrates and condensation rates
lie on universal scaling functions.
