I would use "in" in the first.
I would use "on" in the other two cases.
Should it be:
The pictures are on/in the Power Point Presentation.
The pictures are on/in the laptop.
The pictures are on/in my cellphone.
Why can't it be on the PPT? Isn't a PPT a slide show?
Can you say: The pictures are on the slide show?
Mike didn't say it can't be 'on the PPP'.
He said he would use 'in', and so would I. Others would choose to say 'on'.
You can say 'The pictures are on or in the slide show'.