Herman (Herschel) Kruk was a Polish-Jewish librarian and Bundist activist who kept a diary recording his experiences in the Vilna Ghetto during World War II. Kruk fled Warsaw and relocated to Vilna at the outbreak of invasion of Poland. While confined to the Vilna Ghetto, he organized and oversaw the creation and operation of a library in the Ghetto. He also played an active role in several of the ghetto's social welfare and cultural organizations
„Walk with Kruk“ – it's a smartphone application, which guides you through Vilnius ghetto teritory accompanied by a voice of Herman Kruk. It includes brightest fragments from Herman's diary, sound effects and photographs, that turns on in key ghetto areas and usually reveals a sad and tragic, and sometimes - hope and faith pervaded daily life of the ghetto inhabitants.