If the "Banner" is what I have, it's 3 rotating Alexa Prompts... Today it says
Happy Star Wars Day
"Alexa, May the 4th Be With You"
And the Quotes after that are
"Alexa, Tell me a Star Wars joke"
&
"Alexa, Can you talk like Yoda?"
Other than that... no "ads" or annoying stuff... But like others say, I also only look at the browser app once in a while and the phone app even less often, as the only time I access it is to see what Alexa caught when she failed a command... and it almost always loses the end of what is said, due to someone interrupting with a noise or sneeze or talking on a phone nearby. Over all... I USE the echo items more than I monitor them.