In this paper we first introduce Ls(μ)-averaging domains which are generalizations of Ls-averaging domains introduced by S.G. Staples. We characterize Ls(μ)-averaging domains using the quasihyperbolic metric. As applications, we prove norm inequalities for conjugate A-harmonic tensors in Ls(μ)-averaging domains which can be considered as generalizations of the Hardy and Littlewood theorem for conjugate harmonic functions. Finally, we give applications to quasiconformal and quasiregular mappings.