Every time I send an email from my iPhone, the message includes the footer "Sent from my iPhone" at the bottom. This seems silly to me, and completely unnecessary. Can I change the footer so it’s more personal?
We agree—that footer seems like the is saying “Look at me—I’m cool ‘cause I have an iPhone.” In 2008, that may have been a reasonable assertion, but it’s not the case in 2013. Even more importantly, our guess is that you generally don’t want people to know that you’re sending from a mobile device, which is a good indication (for many people) that you’re responding while away from home. And this is, in general, information you don’t want to be sending out.
Of course, Apple wants everyone to know that you have their flagship mobile device, so they configure the phone to include the obligatory self-congratulatory message in the footer by default. Luckily, that footer information is easy to change (and you should).
On your phone, run the Settings app. Select the Mail, Contacts, Calendars option, and under the Mail section of options, find the Signature option. If you’re running an early version of the operating system (and if so, you should consider upgrading the operating system), you’ll see an option to change your signature. If you’re running a later version, you’ll see an option to select a signature for all accounts, or per account (assuming you have more than one email account configured on the phone). Select the appropriate option, and fill in a new signature, replacing the default text.
You cannot specify a separate signature for new messages as opposed to replies or forwarded messages, and you can't have extra signatures that you can assign individually while writing the email, like you can with Outlook or other email applications.
Certainly, take the time to customize the signature. You won’t be advertising the fact that you’re replying to emails from your phone (indicating that you are perhaps away from home) and you won’t look like a clone of every other iPhone user!