There are three books coming, the fourth planned novel from the game’s creator has been shelved.
Mass Effect: Nexus Uprising is the first novel in a three part series. The book is expected to release on March 28, 2017 and was written by Jason M. Hough and K.C. Alexander. It serves as a prequel to the game’s story.
If your are lost in Andromeda’s nomenclature, the Nexus is a hub for humans, Asari, Turians and other races that come to the Helius cluster in a search for a new home. It was sent to Andromeda early to pave the way for the Arcs. Watch the briefing video to learn more:
Mass Effect: Annihilation, the second novel, by Catherynne M. Valente is expected to release in Summer 2017, with the Mass Effect: Initiation by N.K. Jemesin arriving Fall 2017. It is interesting to see Initiation releasing as a third book – it was originally announced as the first one. Plot details are scarce as for this moment.