I've recently attempted using an iPad to work with sqlDBM and found that, for the most part, it works ... sort of. The biggest issue is that it does not seem possible to pan within the drawing. I also have only worked with relatively small database designs and have not had to deal with many tables. This has allowed me to zoom to extents and just use device zooming to see what I was doing. Although this leads to a bunch of scrolling around on the device viewport to get to the menus and properties entry areas, it is still technically "usable".
If you could come up with either a native app or a mobile friendly web interface, that would be a great improvement.
Customer support service by UserEcho