Sometime in late October/early November, we noticed that our HTML emails seemed to stop rendering correctly when viewing them on the iPhone. Rather than following our media queries, the email looks like a zoomed out column flushed to the left-hand side of the screen--this happens when you open the email for the first time in portrait mode. However, when I rotate the phone to landscape mode, it's as if the queries all of a sudden decided to turn on, and the email resizes accordingly, even when I flip the phone back to portrait mode. Then when I leave the email (return to the inbox) and then re-open the message again, it returns to the incorrect rendering. This seems to happen in the general iOS Mail app, and the Gmail app, so far. I can't seem to replicate the same issues in Android on either the general Mail app, or Gmail android app.
The strange thing is that I coded almost all of these templates in Litmus and previewed them across the different mail clients and devices (yahoo, gmail, outlook, etc.), and after checking them again today, the previews still look completely fine. The queries only seem to break whenever I send a test email to myself or receive a live email, and then I try to view them using my iPhone. I used to test sending emails to my iPhone all the time, and have never experienced the incorrect formatting till now.
Has anyone else experienced this? The only thing that I can think of is that I missed some updates on media queries for iOS devices that require me to adjust my queries, but I just wanted to see if anyone else could also offer some insight.