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