This relates to question:
Using Amazon Instant Video from Amazon Prime on Non-Kindle device
However things have moved on since then. Amazon have now released a version of their Amazon app for use on non-Fire Android phones, and indeed streaming of Amazon Prime is now possible. However the Tablet Amazon app does not have this functionality, even though it is running the same Android OS version (as the scores of negative reviews on the app will testify!) There doesn't seem to be a way to install the Mobile Android app onto a Tablet. It appears that they only allow Amazon Prime to be used from their own Kindle Fire Tablet.
Is there any way I can fool my tablet (Nexus 7) into thinking it is a phone so that I can install the Phone version of the Amazon app and therefore enable Amazon prime streaming?