Icelandic names and consanguinity

In the "searching the news for something not utterly horrible" category, there is this recent story on the Islendiga-App - the App for Icelanders.  Basically, this smartphone app allows any two individuals to "bump phones" and discover how closely related they are as a preventative measure against inbreeding.  Apparently, the app makes use of the Islendingabok, the online genealogical database for Icelanders which cross-references the extensive census records, church registries and personal genealogies with molecular DNA data.  I should note that, in reference to a major personal research interest, Iceland is probably the only western nation where traditional isonymy research is ineffective due to the use of patronymic (and occasionally matronymic) name systems.  In other words, Icelandic children derive their surname from the first name of their father (and occasionally mother).  For example, my surname would be "Thomasson", whereas my son would be "Kevinsson."  This pretty much invalidates the surname as a genetic proxy, although in the case of Iceland the extensive geneaological records provide an alternative for assessing consanguinity via archival methods.