Karp ya fara aikinsa, ba tare da ya sami takardar digiri na makarantar sakandare ba, a matsayin mai ba da horo a ƙarƙashin Fred Seibert a kamfanin Frederator Studios, inda ya gina dandalin rubutun ra'ayin farko na studio da kuma tsara, ya rubuta, kuma ya shirya cibiyar sadarwar bidiyo ta farko ta intanet, Channel Frederator. Karp ya ci gaba da aiki don dandalin iyaye na kan layi UrbanBaby har sai an sayar da shi ga CNET a 2006. Karp ya fara kamfaninsa na shawarwari na software, Davidville, inda ya yi aiki tare da injiniyan kwamfuta Marco Arment a kan ayyukan ga abokan ciniki. A lokacin rata tsakanin kwangila biyu a 2006, Karp ya fara aiki a kan shafin yanar gizon microblogging, wanda aka kaddamar a watan Fabrairun 2007.
Fabrairun 2007