A method for power-saving in a telecommunication network, the network comprising a server (630; 650) and a portable electronic device, - the server (630; 650) comprising a database comprising elements, said elements comprising data entities (122; 124; 126; 222; 224; 226), wherein each data entity is representative of a data information content and a first time period specified by said data entity, each first time period specifying a respective start and end time, wherein the start and end times comprise the lower limit and the upper limit of a time interval defined by the first time period respectively, - the portable electronic device comprising a cache table with cache entries and a graphical user interface for displaying the data entities (122; 124; 126; 222; 224; 226), - the cache table being adapted for storing the cache entries in rows, each row comprising one or more consecutive cache entries, said cache entry is representing the element indicating at least the end time of said element, - the graphical user interface being adapted for displaying a timeline, the timeline representing a time interval defined by a second time period, the method comprising at the device sorting the data entities (122; 124; 126; 222; 224; 226) according to their start times of their respective first time periods for obtaining an ordered set of successive data entities (122; 124; 126; 222; 224; 226), said ordered set having a sort order, wherein the method further comprises, with a current entity being the first data entity in the ordered set that has a start time within the second time period, the steps of: a) defining the first row in the cache table as a current row, b) obtaining from the cache table the last cache entry in the current row, c) comparing the start time of the current entity with the end time indicated by the retrieved cache entry, wherein in case the start time of the current entity is after the end time of the obtained cache entry, adding the current entity to the current row of the cache table immediately behind the last cache entry, wherein in case the current entity start time is before or equal to the end time indicated by the obtained cache entry, selecting the next row in the cache table directly below the current row as the current row and repeating steps b)-c), d) selecting the next data entity in the ordered set of successive data entities (122; 124; 126; 222; 224; 226), said next data entity being the data entity following the current entity according to the order and which has a start time within the second time period, wherein the current entity is now given by said selected next data entity, and repeating steps a)-d), e) drawing the elements represented via their cache entries of the cache table on the graphical user interface, wherein the elements are drawn in rows identically cloning the row structure in which the elements are represented via their cache entries in the cache table, wherein in each row, the elements are drawn in the sequence as they are represented for the respective row by their cache entries in the cache table. - the server (630; 650) comprising a database comprising elements, said elements comprising data entities (122; 124; 126; 222; 224; 226), wherein each data entity is representative of a data information content and a first time period specified by said data entity, each first time period specifying a respective start and end time, wherein the start and end times comprise the lower limit and the upper limit of a time interval defined by the first time period respectively, - the portable electronic device comprising a cache table with cache entries and a graphical user interface for displaying the data entities (122; 124; 126; 222; 224; 226), - the cache table being adapted for storing the cache entries in rows, each row comprising one or more consecutive cache entries, said cache entry is representing the element indicating at least the end time of said element, - the graphical user interface being adapted for displaying a timeline, the timeline representing a time interval defined by a second time period, a) defining the first row in the cache table as a current row, b) obtaining from the cache table the last cache entry in the current row, c) comparing the start time of the current entity with the end time indicated by the retrieved cache entry, wherein in case the start time of the current entity is after the end time of the obtained cache entry, adding the current entity to the current row of the cache table immediately behind the last cache entry, wherein in case the current entity start time is before or equal to the end time indicated by the obtained cache entry, selecting the next row in the cache table directly below the current row as the current row and repeating steps b)-c), d) selecting the next data entity in the ordered set of successive data entities (122; 124; 126; 222; 224; 226), said next data entity being the data entity following the current entity according to the order and which has a start time within the second time period, wherein the current entity is now given by said selected next data entity, and repeating steps a)-d), e) drawing the elements represented via their cache entries of the cache table on the graphical user interface, wherein the elements are drawn in rows identically cloning the row structure in which the elements are represented via their cache entries in the cache table, wherein in each row, the elements are drawn in the sequence as they are represented for the respective row by their cache entries in the cache table.