The present disclosure provides for devices, in particular mobile devices, which may be used in the synthesis of modified nucleic acid molecules, in particular modified mRNA molecules. The device for making the modified nucleosides, modified nucleotides and modified nucleic acids (e.g., mRNA) disclosed herein may be mobile devices comprising at least one sample block for insertion of one or more sample vessels, a device base with electronic control units for the sample block, a voltage supply, and one or more reagent(s) for the synthesis of at least one nucleic acid.