Shift + Ctrl keys in Windows or CMD + Option keys on a Mac will stop the iPhone from syncing when you connect it.
You can always add apps to your iPhone by downloading them from the App store without going into iTunes.
When you get back to the house, the next sync with the external attached will also sync the Apps from the iPhone to the Computer
Greetings, normally I have my music stored on an external HD. When I sync my iPhone the music is synced with the content of the external drive. Were I not to have the drive turned on during the sync, iTunes would delete the music on my iPhone as it would sync the "no music" on my pc with the music on my iPhone. Now I am travelling and will be away from my external HD for about a month. I would like to add some apps to my iPhone but if I do a sync I will lose all that music until I can get back home. Not what I want to have happen. Is there any way to prevent iTunes from syncing the music, ie just letting what's there alone and syncing the rest of the content? Many thanks for any help with this. GL