My wife is a regular commuter on the Southampton-Malaga route operated by Flybe. API information is collected at the check-in desk by the simple expedient of swiping ones passport through a reader.
Squeezyjet could probably do the same if they could be bothered...
Ryan could as well but of course they dont have check-in desks anymore...
API collection is mandatory for all passengers arriving in Spain from all non-Shengen countries including the UK.
If it isn't already required it will soon be required for all flights arriving / departing the UK irrespective of departure country...