"she wants to know what technology airlines can adopt to improve service and attract customers."
You may have to give us a few directions to run in here, "dingducky". Technology and marketing are very wide fields and sometimes poles apart. It may be better for her to ask the customers about airline appeal....rather than the technologists at PPRuNe: Technologists come up with all sorts of zany ideas which are rarely appreciated by the customers. If she has travelled herself, ask your sister what _she_ likes or hates about flying.
Ask her, as a customer, what she appreciates most and we'll be able to tell you how technology can improve these things. If she appreciates safety, then we can make an endless lists of how technology improves safety. Safety may not be a good marketing ploy tho'. An airline may be the safest in the world, but one accident will throw that marketing line back in their faces big time.
On safety: It could be anything from material technology to technology used for training pilots/engineers. It could be carbon brakes with better stopping power, it could be fire resitant materials in seats, it could be better survival gear.
Once people get over their fear of flying, then they start to think about more frivolous things, such as comfort, entertainment, nice meals and getting to their destination on time. Technology can help in all of these departments. I can see two paths here.... Technology which will attract the customer and technology which will keep the passengers coming back once they've experienced the technology. The former is probably the harder nut to crack. It's difficult selling technology to people who haven't flown before and haven't got a clue how a technologically advanced widget will improve their flying experience (Word of mouth, however, from those who have flown before and have experienced the effect of this technologically advanced widget, can help persuade a first-timer to fly airline X).
On comfort: It can come in the form of better airconditioning, better soundproofing materials (higher noise levels cause more stress), more stable aircraft which don't leave the sick bags full... and better seat design (which almost gives you the impression that they are actually designed for sleeping on as well as sitting in. I wouldn't be overselling the electrically reclining seats though... They are much more likely to break down than their manual counterparts). Having an advertised feature not work on your particular flight can be a real slap in the face... The same rigorous testing of airplane components does not always apply to cabin fitments. Also, on the comfort angle, technology can make a cabin seem airier and make you feel like you're not travelling in a metal tube.
Technology can give you better, faster, more reliable, human friendly computers which will help the airline take and keep your booking.
Better technology can give you better meals. Better refrigeration can keep food fresher. Better ovens can heat the food faster and not dry it out (Steamer ovens are the latest fad on our airline). But all this preparation is wasted if you can't get it down the aisle before it goes cold... or before your ice cream melts. Technology has given us heated carts, dry ice and better insulation.
Better technology can give you better entertainment. You now have "video on demand" at each seat instead of having to wait for a blurry movie to appear on a tiny screen 20 seat rows away. Technology can show you where you are and how long it will take you to get to your destination, by using the airplane's navigation systems to put a "moving map display" up on your personal video screen. Technology can put a telephone at each seat, so you can tell the folks back home what a wonderful time you're having. Better technology lets you pay for your duty free with credit cards, instead of making you scrabble around in your purse/wallet for the correct currency.
Technology put vacuum toilets on aircraft....so now you don't have to worry about the sewer tank being directly underneath, drenching you with blue water when you hit turbulence. It puts natural white light in toilets so you don't scare yourself silly looking at yourself in mirror in ghastly green fluorescent light (which accents the colour of your eyes on the "redeye" flights).
As the previous gentleman stated... Truly a Pandora's Box, but....
I hope this helps.
Rgds.
Q.