I think it's more that, given that we are going to be carrying a phone anyway, we might as well look into what features would make it most useful in a disaster.

My picks would include:

• Small size. It can't help if it's not with you.
• Long battery life.
• Easy recharging, eg through USB.
• FM radio (for picking up emergency info).
• E-book reader with reference works.
• E-books and games for entertainment (disasters can be dull).
• I've not come across a phone with a digital compass, but on mine I have a Java app which shows sun and moon positions which can be used to navigate when they are visible in the sky.
• GPS. (Find out what it can tell you when it can't get a cellular connection. Can it give a grid reference without maps?)
• Google Maps or similar. (Useful even without GPS.)
• Consider getting a digitised local map for when comms are down. (I've not found a good solution for this.)
• Camera for documenting what happened. May be important later. If you are bitten by a snake, take the snake's picture. It may help the medics identify which antidote you need.
• Torch. Mine doesn't have a proper torch, but it has a crude flash in its camera. Plus the backlight is bright enough to navigate indoors, if your eyes are dark-adapted.
• The ability to make phone calls.
• The ability to send text messages (these often get through when a phone call won't).
• Web access, with links to news and reference sites.

Reference material can be invaluable, especially if it can help you avoid getting into difficulties in the first place. Eg weather updates, or local tide tables if you are by the sea.

Communications can be invaluable, too. But also think of features that will be useful when the phone network is down.