Crossway who publish the ESV Bible write...
As of Monday, April 13th, Crossway now offers the ESV Global Study Bible free of charge, accessible via a variety of digital platforms.
In providing free access to the Global Study Bible, we want to equip the global church with theologically rich, gospel-centered content aimed at helping God's people better understand the Bible and apply it to their own lives.
There are three ways people can access the Global Study Bible:
On a computer via ESVBible.org
On an iPhone or iPad via the new ESV Bible app
On any digital reading device via the free e-book
It is our prayer that the Global Study Bible serves Christians around the world as they read, study, and teach the most important book that has ever existed: the Bible.
You can find links to the various formats here