We review the determination of the low-energy pion-nucleon scattering amplitude using Roy-Steiner equations. In particular, we focus on
the phenomenological determination of the pion-nucleon $\sigma$-term, derived in combination with modern precision data on pionic atoms, and
address some of the most frequently asked questions regarding our analysis. Finally, we discuss recent applications to nucleon form factors and the determination of low-energy constants in chiral perturbation theory.