Fans sing along to popular track 'Titanium' to round off an epic Summertime Ball. This image appears in the gallery:David Guetta Live At The Summertime Ball 2014 7. Fans sing along to popular track 'Titanium' to round off an epic Summertime Ball. Picture: PA 9 images See the full gallery: David Guetta Live At The Summertime Ball 2014