Modifications in mRNA constitute ancient mechanisms to regulate gene expression post-transcriptionally. N ⁶ -methyladenosine (m ⁶ A) is the most prominent mRNA modification, and is installed by a large methyltransferase complex (the m ⁶ A 'writer'), not only specifically bound by RNA-binding proteins (the m ⁶ A 'readers'), but also removed by demethylases (the m ⁶ A 'erasers'). m ⁶ A mRNA modifications have been linked to regulation at multiple steps in mRNA processing. In analogy to the regulation of gene expression by miRNAs, we propose that the main function of m ⁶ A is post-transcriptional fine-tuning of gene expression. In contrast to miRNA regulation, which mostly reduces gene expression, we argue that m ⁶ A provides a fast mean to post-transcriptionally maximize gene expression. Additionally, m ⁶ A appears to have a second function during developmental transitions by targeting m ⁶ A-marked transcripts for degradation.