Designing and coding HTML for email is hard enough just when you’re dealing with all the quirks that desktop and webmail clients toss your way.
Introducing mobile into the mix can add a lot of time and frustration.
We’ve put together this handy chart that covers mobile email compatibility basics like image blocking, preview text, alt text, and more.
HTML: This column is an indication of native HTML support on the device. The great news is that most modern mobile operating systems support HTML and CSS, some even better than desktop clients! The days of worrying if your recipients will receive a garbled text-and-code mash on their Blackberry are mostly over. As long as your recipients aren’t reading on a Blackberry that’s more than a couple years old, they’re most likely to receive your HTML version if they’ve enabled the option on Blackberry 4.5/5.
Images: While HTML support in mobile is mostly good news, the bad news is that image blocking is back in a big way. The only mobile OS that doesn’t block images by default is the iPhone/iPad. However, of those devices that block images, most offer a big touch-friendly button to turn them on.
Alt Text: If you’ve been designing email signatures for the desktop for a while, you probably know the fine art of alt text. Unfortunately, only Android will display alt-text behind a blocked image.
Preview Text: Preview text has gained a ton of traction in recent months due to it’s prevalence in Outlook, Gmail and the iPhone. It shows up right after the subject line, and pulls in the first few lines of live text from your email to give readers a “snippet” of what’s in the email. It’s a great way to pack more punch in your email, and it will show up in iOS devices as well as Windows Mobile 7.
Scale: While the iPhone zooms into your email and fits the email to the width of your screen, most other devices will display the upper left-hand corner of your email, leaving users to scroll left-and-right in addition to up-and-down to view your entire message. You could think of this space as the preview pane, reborn for the mobile age.
Modify Fonts: Reading email on a tiny screen is hard. Every mobile OS will modify your fonts to some degree, although it’s a bit of a mixed bag. iPhone and iPad have a 10pt minimum font size and will auto-adjust anything under that size, often breaking your email signature table design. I observed text being condensed, breaking at random intervals and other unfriendly behaviors, but nothing that seemed consistent or predictable. The best course of action is to plan for unruly text behavior in your design, and learn to accept that your fonts may not be the size or shape you intended.