Hi Graeme.
You need to thin out the apples. This may take place naturally, as
part of the "June drop" (somewhat delayed by the wonderful weather!),
however you may need to supplement this natural process whereby the
tree sheds excessive amounts of fruit to protect itself. The RHS
website and various others have lots of advice about this. The idea is
1) to thin out sufficiently so that all the remaining fruit has access
to air and light; 2) to prevent the branches from snapping under the
weight of all the fruit. I tend to remove enough fruit to allow an air
gap around each remaining fruit, and still harvest plenty. See
http://www.rhs.org.uk/advice/profile...nningfruit.asp for
further details.
-- Keith