There are two main apps for First Aid and they are available on iPhone, iPad, Android and Blackberry and they are all free.
It seems like a no brainer, why would Â you not have at least one of these on your phone?
No point writing long paragraphs, download them and see which you prefer:
There are apps for Windows devices but neither SJA nor the Red Cross make them so I am not happy linking to them. Just search the app store and you will find some.