Denis Jakus has done some testing with a Nokia C7, a Symbian S^3 device. He reports that NS Basic/App Studio seems to run OK on it: apps deploy normally, can be added to the Home page and run offline.
He wasn’t able to get definitive results on SQLite databases before he gave up the device.
The latest browser from Symbian is WebKit and HTML5 enabled, so this is good news.
Let us know if you have additional information on Symbian!