ios is underlined because it is grammar checked to iOS. I think capitalization matters to autocorrect.

Ps. Posted on iOS not android

Pps. Android is not spellchecked when lowercase but iOS is?? ios android

Ppps. Why is Ps allowed but not Pps?

Pppps. This is getting ridiculous.

Ppppps. Haha I said pp

Pppppps. This is the last one unless someone comments something that makes me want to edit this comment