In their FAQ regarding if they have access to account information... "Yes. But with 100s of people using the app, it's really not interesting to run after your details."
I would expect that in a lot of application's it is possible to pull out client data one way or another. The way this is written makes it sound like client details are sitting on a desk and the only reason they aren't rooting through your details is because you aren't interesting enough.
Well.. what happens when you apparently offend the designer on HN and become of interest.
The answer should be technically yes but no. A developer could engineer access or pull data from a client database. However, breaches like this aside, there is no formal way to access your account or see your data.