Symantec has grappled with the same issue of whether or not to use StuffIt Expander 5.x that I confronted last week. They have chosen to use the 5.x technology, which means that you will need StuffIt Expander 5.x to decompress their March 1999 virus definitions (just released). (Thanks, Monty Solomon.)
Is your phone battery always at 4 percent?
These battery packs will give your device the extra juice to power through all of those texts and phone calls.