Planetary nebulae (PNs) reflect the evolutionary history of their
progenitors, they are probes of low- and intermediate-mass stellar
populations, and they are the major contributors to carbon and nitrogen
recycling in the Universe. Galactic PN studies indicate that their
morphology is linked to stellar evolution and chemistry, but the very
large uncertainties in the Galactic PN distances, and the selective
absorption of  PNs in the Galactic disk, hamper the reliability of
these results.

The Magellanic Cloud PNs are within reach, and their morphology can
be measured with the Hubble Space Telescope, while their distances are
known and their reddening not forbidding. They are thus the ideal probes
of stellar evolution of low- and intermediate-mass stars, and they are
also probes of different metallicity environments.

Our Hubble survey includes ~80 LMC and ~30 SMC PNs, whose morphology,
size, energetics, and in some cases central stars properties, UV
spectra,
and dust properties have been studied. This sample includes  about half
of all known LMC and SMC PNs. I will present observations and analysis
from this survey, and discuss scaling laws between PN parameters, the
relation of PN properties to the nature of their progenitor stars, the
distributions of PN morphologies in different galaxies, and the PN
luminosity function (a commonly-used extra-galactic distance indicator)
and its dependence on environmental metallicity.