Only Binaural waves require the headphones, isochronic tones do not.
The better deal is MindWave although it does require the headphones. I will also mention that binaural tones are well studied and DO have a scientifically proven effect. I will also let you know that you don't need to be listening while laying down, the whole methodology of binaural beets is that they entrain the brian waves to mimic them. Once your brain waves are entrained to the new frequency they will remain at that frequency unless you do something to change them. Ie if you're sleepy you need to do something to wake yourself up, you won't just suddenly become wide awake just because you stop listening. So you can just sit back and relax reading a paper or surfing the internet while listening and when you find yourself falling asleep just take off the headphones and go to sleep.
One final thing, the brain is most likely to entrain to an outside stimulus when that stimulus is at least somewhat close to the brain pattern currently active. So you'd probably want to start out using clean slate then move on to deep medication then move on to sleep induction (three different settings of the app), this will stage down your brain patterns and lead to the most likely success.
The only gripe I have with MindWave is that it attempts to stage you down on it's own using a looped track but the loop isn't long enough, which means just when you're really getting sleepy it shoots up to a high frequency as the loop starts over (I'm speaking specifically on the sleep induction setting).
