you'll find it's really worth your while to invest in one - particularly one where english and norwegian are interchangeable to translate from. as for apps - check out ordnett's dictionary (try searching "ordnett norwegian"). on the computer, ultralingua offers a great one - both are around $30. both have example sentences for better context too which is a huge help. since you're fitting yourself into a new language you still want to be you. if you have a quick-and-ready program or app to pull from (instead of loading a page online that might not be interchangeable or might not give you sentence examples for better context), you can make flash cards online or in an app very quickly with words that are most relevant to you as you go.