Just came across it.
http://bitshift.bplaced.net/en/dslr-remote.htm
Only for Android smartphones/tablets. IR goes out via headphone jack. An English DIY
How-To for that dongle is available with heaps of self-explanatory photos. And a whole range of DSLRs are listed as
compatible in "passive mode".
Smartphones whose audio level is too low - he says, this is true particularly for some newer smartphones/tablets - are special. ..
Particularly interesting for Sony Nex-5N owners. Nex-5N only has IR, no USB or Wifi control is possible. So this app plus the DIY audio-to-IR dongle, parts all at Jaycar probably, offers IR intervalometer capabilities!
Attached a screenshot specifically for the connection to a Nex-5N. It's in German, as well. But simple as.
Verzögerung = Delay
Verschluss = Shutter, here it means exposure time
Intervall = Interval for breaks between exposures. Has to be set to anything higher than 0 if you want to shoot more than 1 photo.
Aufnahmen = number of photos
Easy as. And free! Donations appreciated.
So sad I own an iPhone... can't test/use this app with my Nex-5N.