How to change default program on IPAD?

Hi there,

I want to change the default program for opening .RTF files *ON MY iPAD* (not a Mac).

Currently, .RTF files open in the PDF reader app (‘documents’) by default and can’t find any settings in any program (or in the ipad settings) to change this.

All I want to do is have all .RTF files to open, by default, in Word. I have never had so much trouble doing such a simple thing - PLEASE HELP!