You can use "Barcode Scanner" (ZXing project) available in the Google App Store (free) I'm sure there are others that will work, but I like this one for scanning.
In the app settings turn on "Add to History" and "Bulk Scan Mode"
Scan the ISBN codes, then go to "History" and click the share icon.
Email your history to yourself. It will come in as a .csv file - the text will show up in the email, but there will also be a file atteached that you can open.
Copy the ISBN numbers from the file and paste them into your "import books" box, click "Add Books."
Done. :)