I received the following reply from Kobo Support to my question, "Will I be able to download an Android Kindle app in order to read Kindle (AZW) formatted books from Amazon?"
Thank you for contacting Kobo we sincerely apologize for the delay in responding to your email.
Please note, Amazon devices cannot be used with kobos devices its locked to Amazon network only.
Kobo Vox supports the following file formats:
For eBooks: EPUB, Fixed Layout EPUB, SMIL (multimedia EPUB) (.epub)
Text files (.txt)
The Kobo Team
This appears to contradict an earlier statement by their CEO so I am somewhat doubtful as to it's veracity but I am going to hold off for now until I know for sure.