  We present recent measurements of $\tau$ physics at the Belle II experiment
at SuperKEKB. Measurements include a test of $e-\mu$ lepton flavor universality
in $\tau$ decays, a search for the lepton flavor violating $\tau \rightarrow
\mu \mu \mu$ decay and a precision measurement of the $\tau$ lepton invariant
mass. In addition, we present a measurement of the low multiplicity decay cross
section $\sigma(e^+ e^- \rightarrow \pi^+ \pi^- \pi^0)$, a key input in the
theoretical prediction of the anomalous magnetic moment of the muon.
