2D multilayered perovskites share similarities with 3D perovskites including direct electronic band gap, sizeable optical absorption, small effective masses, Rashba-like effects. A recent classification of multilayered perovskites as Ruddlesden-Popper, Dion-Jacobson and \"Alternative cations in the interlayer\" was introduced in relation with the chemistry of the compounds or the crystallographic order along the stacking axis. Interestingly, they exhibit other attractive features related to tunable quantum and dielectric confinements, strong lattice anisotropy, more complex combinations of atomic orbitals and lattice dynamics, extensive chemical engineering possibilities. This will be illustrated by recent combined experimental and theoretical studies on excitons, formation of edge states, hot carrier effects and carrier localization. 2D multilayered perovskites have exhibited improved device stability under operation. More, combined in 2D/3D bilayer structures using new versatile growth methods, excellent solar cell device stability can be achieved. Band alignment calculations nicely explain the difference of performances for ni-p or p-i-n devices. The lattice mismatch concept can provide further guidance for the choice of the proper 2D/3D combination, leading to enhanced stability for 3D-based solar cells.