Thanks all for the good wishes and offers. We will definitely get back to you.
We are currently testing on galaxy nexus phones, a nexus 7 (my son got one when he was at the Google I/O conference in June), and an HTC Hero (*old* phone running 2.1) to ensure backwards compatibility. Once these are working to our satisfaction, we will test on a Kindle Fire (required for Amazon approval) and some Samsung and HTC gingerbread phones (V2.3). I don't think that we have access to any Honeycomb (V3) tablets, but I suspect that there aren't a lot of them remaining in the wild.
I suppose that I shouldn't be so free with the "we"s. I am doing the calibre programming required by the app, and testing the app on my galaxy nexus. My son is doing the Android work, which is good because unlike me he is skilled in that arena. His company,
MultiPie Ltd, will handle distribution, development, and maintenance of the app.