Timeline Eons promises nothing if not the whole world. The app presents the entire history of the universe, from the Big Bang to our present 21st-century travails, scaled down into a graphical representation on your phone or tablet's relatively compact screen.

The app's default view presents a timeline across the top, the scale of which can be pinched and dragged according to the user's whim (so, for example, you can set each interval to represent anything from a single day to entire millennia). On the timeline are listed key events and periods in history. These tend to be focused more on Anglo-Saxon events -- for instance, the current American president is listed along the top, while a disproportionately high number of events concern US history -- but traveling back further into the past results in a more international scope. Many events are illustrated with a picture or photograph, while some, such as the premiere of Verdi's Rigoletto in March 1851, are accompanied by a brief audio recording. Alongside browsing through the timeline, there is a search function, and there's also the option to tap on a particular entry and search for further information via Google or Wikipedia.

The app does have a few drawbacks. The app is far better on the increased screen size of the iPada; using it on an iPhone was quite a fiddly process, and it ran quite slowly on the 3GS model we tested it on. As mentioned earlier, the Anglo-centric nature of the material included does tend to grate after a while.

Timeline Eons is available on from the App Store on iOS in a free, ad-supported version, and there's also a premium version, minus the ads and with the option to add your own things onto the timeline, available for £3.99 / $5.99.