Tree of Life App is an interactive and illustrated family-level phylogeny of living beings based upon a synthesis of data from thousands of published studies from the primary literature. Main groups of organisms –from Bacteria to Vertebrates- are displayed in the initial tree as collapsed branches that can be opened to view family level relationships. Over 7000 families are included in the current version. The interactivity and contents of Tree of Life App include the following features: -Zooming in or out in order to explore a very large tree -Tapping on the pictures to see family details such as common names, and quick links to Wikipedia (internet connection is required for this feature) -Collapsing clades into single branches to summarize or hide undesired details -Viewing subtrees of special interest -A search feature enabling users to find specific organisms either by common or scientific family names -A time scale to determine divergence dates among lineages and dates of extinction of fossil families Tree of Life App is constantly being updated to include recent findings, guaranteeing to illustrate the most up-to date state of the art about evolutionary relationships among living beings.