The brain produces electrical signals. These signals change depending on what we are doing and what mental state we are in. For instance when we sleep these signals are different from when we are awake. This brain activity can be measured with EEG. It will output in Hz (Hertz - cycles per second) these electrical signals. The most dominant brainwaves will tell us what sort of state a person is in. The slower vibration (lower Hz), the more relaxed that individual is. Using audio technology we get the brain to start following the beats or pulses in a sound if done exactly right.

Alpha brainwaves are resonating just below beta brainwaves at the frequency range of 8Hz to 12Hz on an EEG. Beta brainwaves are the normal, waking life, active, rational thinking and problem solving brainwaves that are dominant in most people throughout the day. Alpha brainwaves begin to show up when relaxation occurs. Often times the simple act of closing your eyes can product spurts of alpha waves. Taking a few deep breaths or consciously relaxing will do the same. When alpha waves become dominant, the body and mind are usually comfortably relaxed.
Most programs start at a work/life busy brain Beta frequency of twenty light flashes per second (20Hz) and slowly ramp them down to Alpha (relaxation and meditation) at 8-12 HZ, Theta (deep relaxation and dreaming) at 4-8 Hz) and Delta (dreamless deep relaxation) of .5-4Hz. We have taken measurements at Mass General with state of the art EEG equipment and have seen a slowing of the brain waves from Beta to Theta in two minutes and complete brain wave harmonization in the left, right, anterior, posterior and occipital regions of the brain.

And this is exactly true. Have you heard about walnuts improving your memory and being extremely healthy for you when eaten raw? A doctor can confirm this information for you. Try eating too many of them, especially in the afternoon – you will end up nauseous, and if you have a relatively low blood pressure, you can even drive yourself to a nearly unconscious state. Except for their healthy benefits, walnuts tend to lower blood pressure, and when eaten in excess, they can have some very nasty effects on your body. Does this mean you should never eat walnuts, and never benefit from their wonderful qualities? Of course not!
Beta stimulation: There is evidence that stimulation within the beta range can improve attention, measures of intelligence, relieve short-term stress, decrease headaches, and decrease behavioral problems. Some evidence even suggests that beta could decrease emotion-based exhaustion. Many people with slower frequency brain waves may benefit from regular beta stimulation.
To get a full answer you should really get in touch with the owner of the app, because it does really depend on how their track is constructed and how they intend it to work. I have one 50-minute sleep track which takes you down into delta ( and that is designed to just get you to sleep, so you just let play until the end. If you played that track on repeat it might make you jump and wake you up, as the track begins at a higher frequency. I have another 8-hour sleep track which is meant to be played all throughout the night ( So it does depend on the individual track you are using.

Monaural beats have similarities to binaural beats, but the two separate frequencies are delivered through a pulse pattern and mixed before they reach the listeners ears, resulting in the advantage of being audible without stereo headphones. However, using stereo headphones intensifies the effectiveness of monaural beats and is recommended for the best effect. 

Creativity: Measuring “creativity” is likely subjective, but many people stuck in a certain dominant brain wave may benefit creatively from shifting the brain wave dominance. Someone who has excess beta waves may fail to relax enough to access certain (potential) creative properties associated with increased alpha waves. Similarly someone stuck in a slow wave state may benefit creatively from increasing beta waves.
So using the example track above, the right ear is sent a 20Hz beat, compared to a 10Hz beat in the left ear.  As the right ear receives the higher frequency of beat, this works to increase the speed of the ‘left' brain hemisphere, which can be helpful for people with conditions like ADD, who are often found to have an abundance of slow wave activity in the left brain.

Deep relaxation is a major benefit resulting from the brain’s cortical frequency following response. By selecting the desired rate the brain, via the frequency following response, will tend to mimic the rate it is exposed to and thus enter that brainwave state. This helps to explain why this technology can produce benefits commonly found with meditation. One of the most valuable benefits of consistent  brainwave entrainment is that we are able to experience and recognize the various states of consciousness. With practice we can learn how to re-create these states.

By exposing an individual to repeatedly external stimulus which can be flashing lights and/or recurring sounds, the entrainment process consists in pushing the brain to adjust to match the frequency provided. Unlike other forms of neurotherapy which require the individual to actively respond to stimulus, entrainment creates an immediate neurophysical response which is instinctive and effortless for the person being provided with the light and/or sound combinations. The key outcome of the sensory stimulation is known as the ‘Frequency Following Response’.
Use Holosync® to accelerate the process (our data tells us that Holosync® creates the benefits of traditional meditation about 8x faster, but without spending several hours each day). Holosync® is faster, and it is easier. And, because you begin, the first time you listen, meditating like a 30+ year veteran, you see results quickly. Finally, Holosync® feels so good, and in fact causes you to feel good for the entire day when you use it, that the problem of getting yourself to meditate each day disappears.
AVE is capable of producing situationally appropriate brain wave frequencies through the process of entrainment (the tendency of physiological processes to mirror environmental stimuli). AVE also increases cerebral blood flow (blood flow in the brain) and increases the metabolization of glucose in the brain for improved functioning of the neurons. The combined outcome of these processes is improved mental performance. It is an effective, inexpensive alternative therapy for many disorders such as anxiety, Attention Deficit Disorder (ADD), Seasonal Affective Disorder (SAD), PTSD, Fibromyalgia and chronic pain. Our AVE devices are also used successfully to boost physical performance for athletes, academic performance for students and cognitive performance for seniors.
Binaural beats require two separate tones from two sources that are combined inside the listener’s brain to form the target tone. The lower frequency sound is called the carrier tone, and it is combined with a higher frequency sound known as the offset tone. Because of this, binaural beats must be listened to with stereo headphones or the effect is lost. Binaural beats create a hypnotic effect, but they are not the most effective tool for brainwave entrainment, and binaural beats are often ineffective for people with hearing loss.
The functional role of neural oscillations is still not fully understood;[6] however they have been shown to correlate with emotional responses, motor control, and a number of cognitive functions including information transfer, perception, and memory.[7][8][9] Specifically, neural oscillations, in particular theta activity, are extensively linked to memory function, and coupling between theta and gamma activity is considered to be vital for memory functions, including episodic memory.[10][11][12]