iFirstAid was developed in the aftermath of the London bombings on 7 July, when the charity registered a 25 per cent increase in enquiries about first-aid courses.
"It's something we had thought about for a while," said Richard Even, director of training at St John.
"But recent events and the widespread adoption of this kind of broadcasting by organisations such as the BBC led us to believe that the time had come."
The exercise, which was recorded at the Skyline Audio Post in London, was also surprisingly cost-effective, Even added.
Whereas the charity might expect to pay tens of thousands of pounds to record a first-aid video, the production costs for iFirstAid were just a few thousand pounds.
The first-aid tips are divided into several two-minute segments. Users are told how to carry out a primary assessment of an accident scene. Guidance on how to treat burns, bleeding and shock is also available. St John intends to update the service over time to include initiatives such as seasonal first-aid advice.
"The iFirstAid tips are no substitute for first-aid training, but it's useful to have a reminder to give you confidence and reinforce your knowledge," said Dawn Upton, the voice of iFirstAid.
Apple has agreed to make the information available for free on iTunes. Owners of MP3 players and mobile phones can download the tips from the charity's website.