Android Browser -Can it be set to NOT open new tabs?
There's no such setting in the Android browser as far as I know. You could try using a different browser that does not have tab functionality, like Orweb, although that may have issues with cookies and may complain when the phone is not connected to Tor.

If that doesn't work, you could try Firefox with the Tab Killer extension; it may not work on mobile, but it might be worth a shot.