  An angular analysis of the $B^{0}\rightarrow K^{*0}(\rightarrow
K^{+}\pi^{-})\mu^{+}\mu^{-}$ decay is presented. The dataset corresponds to an
integrated luminosity of $3.0\,{\mbox{fb}^{-1}}$ of $pp$ collision data
collected at the LHCb experiment. The complete angular information from the
decay is used to determine $C\!P$-averaged observables and $C\!P$ asymmetries,
taking account of possible contamination from decays with the $K^{+}\pi^{-}$
system in an S-wave configuration. The angular observables and their
correlations are reported in bins of $q^2$, the invariant mass squared of the
dimuon system. The observables are determined both from an unbinned maximum
likelihood fit and by using the principal moments of the angular distribution.
In addition, by fitting for $q^2$-dependent decay amplitudes in the region
$1.1<q^{2}<6.0\mathrm{\,Ge\kern -0.1em V}^{2}/c^{4}$, the zero-crossing points
of several angular observables are computed. A global fit is performed to the
complete set of $C\!P$-averaged observables obtained from the maximum
likelihood fit. This fit indicates differences with predictions based on the
Standard Model at the level of 3.4 standard deviations. These differences could
be explained by contributions from physics beyond the Standard Model, or by an
unexpectedly large hadronic effect that is not accounted for in the Standard
Model predictions.
