Camera Phone Technology

[uncle al]

My nephew has sent me a camera phone photo that shows a "ghost" in the background
I think he's winding me up because I know there are "apps" that do everything these days, including magicg tricks using old photos (psypic I think)
Does anyone know of an app or trick to add images to camera phone photos (not having been altered on any pc)?

[bibblebub]

How do you know that it hasn't been altered on a pc? It's just as easy to upload a pic from the pc to the phone as it is to download one from the phone to the pc.