Well... we are not really Apple people per se, we are users just like you who volunteer to answer questions and when we answer them and help someone they "reward" us by clicking on this helped or solve the problem. We do not work for Apple. Actually I am retired so I don't work at all.
You can certainly delete all non native apps on your phone and download them again. When you press and hold any app they will start vibrating and the ones you can delete will have an X - click to delete the ones you want. When you are through, click the Home button. You can certainly delete Keynote, Numbers, and GarageBand and add them back later when you return if you like. Enjoy your trip....