Albert,
I am using the I6 and I cannot delete built in apps as far as my experience
goes. You can delete files on the home screen by tapping the file twice
rapidly and holding your finger down on the second tap. Then, if you let
your finger up, it should say, "Moving that filename." Wait for a second
and just touch the screen right where you tapped it twice and it will say,
deleting file editing. My wife is using the I5 and she said this command
did not seem to work until the latest version 8.X software I O S came out
for the I5 and I6. I haven't tried it but I bet the same double tap will
indeed delete an built in app but I could be wrong. At least now it prompts
me before I try and delete any app. HTH
Phil.
K0NX