I will give an introduction to modular symmetries and how these symmetries can be interpreted as a family symmetry. Afterwards, I will focus on an SU(5) model in 6d where the two extra dimensions are compactified on a T_2/Z_2 orbifold, with a twist angle of \omega= ei2pi/3. Such construction suggests an underlying modular A_4 symmetry, leading to an effective \mu-\tau reflection symmetry at low energies. This implies maximal atmospheric mixing and maximal leptonic CP violation. Slides can be found here.