We present a measurement of angular observables and a test of lepton flavor universality in the $B\to K^\ast\ell\ell$ decay, where $\ell$ is either $e$ or $\mu$.
For the first time, the angular analysis in the $B\to K^\ast\ell\ell$ decay is performed separately for the electron and muon channels.
The analysis is performed using a data sample corresponding to an integrated luminosity of $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the asymmetric-energy $e^+e^-$ collider KEKB.