Personally, I believe that taking the action to open your coat and draw another persons attention your gun is no different than pulling it out and waving it in front of someone nose to get their attention with it.
Depending on the state, just saying I have a gun and I'll use it may involve a minimum amount of jail time due to provisions for using a gun in the course of a crime.
On the other issue, I really do not understand the battery complaints for the iPhone. I've never owned one but I do use a Samsung Omnia as my personal phone and have had a couple other smartphone for work, Blackberry Storm and an LG model, and not one of them has ever lasted the whole day on one charge if you are actually using the phone to do allot of email, surf the web etc. Just making a few calls of 15 minutes or less and having push email or 10min email auto-check running and viewing/replying to emails as they arrive saps the batteries on all these phones to the point of needing to have a car charger, USB cable to charge from laptop and extra ac chargers (home and office) for normal business use.
Forget actually trying to do things like watch a movie which will zap a battery from full charge by the time one 2 hr movie plays.