No music on Ipad and Iphone - where do I turn on HTML on Message box?

I don't have either -  an Iphone or an Ipad  ( I'm so deprived, but I don't want either ) - I am only going  by what I have been told.
"The message says " they need Flash - they downloaded Flash and still nothing.

I thought maybe the card senders could do a hot link to the music ( so they don't have to copy & paste )  with the message, but HTML is not turned on.
Is there somewhere where I can turn on HTML on the message box?
I converted all of the audio to .MP3.
Does anyone have a workaround for this?
I am using a Laptop and PC and the music works.

Thank you!