Some good free Bible concordance apps are MySword Bible and And Bible for Android devices, as well as Holy Bible and Mantis Bible Study for iOS devices. MySword Bible supports search and highlighting. It also lets readers enter their own notes and thoughts.
As of 2015, And Bible includes over 40 versions of English Bibles. It features an extensive collection of dictionary and Bible commentaries. Holy Bible for iOS supports searching, highlighting and social media sharing, and it lets readers back up their notes to iCloud. Mantis Bible Study supports offline viewing and comes with the full version of the King James Bible. It allows readers to highlight and make notes.