If the device is left to "go to sleep" with the app running, when he presses a key to "wake it up", it comes back on with the today screen showing, but the hard keys do not work as he expects (I suspect my app is still trapping them).
I had that argument set to false as I was trying to use one object to cover several forms. I hadn't realised that doing that would trap keys elsewhere.
I've now got seperate Hardkey objects for each form, with the argument set to true for each one's new1 call so I am hoping all will now be well.