This is one of the most inexplicable features on iOS: have you ever tried to paste your carefully planned and designed corporate HTML signature into iOS Mail? If you did, you probably had a very disappointing experience.

This is the result you will achieve in the end:

A broken signature.
A broken signature.

The process to get this working the way you probably want it is very simple:

  1. Go to your sent mail, and select the signature you already used on your desktop
  2. Paste it in the Mail signature settings in iOS
  3. Above all, surprisingly, the most important part at this point is that you have to shake the phone!
  4. After shaking the phone, press “undo” in the popup menu
  5. Problem solved!

Enjoy your signature the way it was meant to be!

This is a really weird behaviour. I still cannot understand the reason behind this, albeit it might be connected somehow with the attempt to remove possibly incompatible formatting with some web client. The weird thing is that this feature looks like a hidden cheat code from an old videogame more than something related to a typical business feature. That being said, we never encountered further problems with this technique.