The 20th anniversary of the iMac reminded me that while many people capitalises the word “iMac” as Apple would like, including John “I never capitalise trademarks the way companies like” Gruber, nobody uses the article-less form that Apple does:
So you can do everything you love to do on iMac.
I, like many other people, would insert ‘an’ in there, and Apple have lost that battle. There’s probably somebody in Elephant who has chosen that hill to die on.