Lullaby for my baby

As a parent raising a child, I made an application called ‘Lullaby for my baby’, to help other parents.
It has mainly five (5) features.
Firstly, it is white-noise. For those babies under 3 months old, they easily fall asleep while listening to mother’s heartbeat, water drops, cloth brushing sound, etc. So, it is equipped with a function to play up to maximum three (3) sounds (you can select from fifteen (15) sounds of white-noise, that are similar to the environment inside mother, such as TV noise, cleaner sound, heart-beat, vinyl bag, etc.) at the same time
(For your information, turning on music mixed with TV sound, water droplet, and heart-beat worked great on my baby)
Secondly, it is lullaby. This app is equipped with most well-known nineteen (19) lullabies (English songs, classic, Music Box, etc.). It also has a function to record lullaby in mother/father’s voice and to play it repeatedly.
Low-toned father’s voice is better transmitted to fetus, such that it reacts far better than mother’s voice. It is known that it also helps baby’s brain development. (For your information, I recorded five (5) children’s songs and my wife turned them on while I was at work. Later she told me that it reacted quite well to my voice.)
Thirdly, it is a baby toy. Babies tend to cry and bellow until 100 days. Parents try almost any possible way to soothe baby.
Usually, playing with a rattling or whistling toy may stop baby’s crying.
So I inserted a function of three baby toys (rattle, duck toy, whistle). (for your information, it worked great with this toy function whenever we are moving in a car, or when a baby starts to cry)
The fourth feature is singing "Happy Birthday." Have fun celebrating your baby's birthday and play a game of "blow out the candles."
Fifth option is the sound of animal / vehicle / musical instrument. Kids learn to love animal sound after 6 months old.
So, I bought a sound book for my baby, but it was too heavy and too large. So, I created an app and put the file in it.
Turn on the sound of animal/ vehicle/ musical instrument using your smart phone. ^^ (my son can easily focus on music whenever I turn on animal sound while we are driving)
1. Possible to turn on music up to a total of three (3) different sounds at the same time, choosing from fifteen (15) soothing sounds
2. Built with nineteen (19) music including English lullaby, classic lullaby, organ (music box)
3. Possible to record mother’s or father’s lullaby
4. Possible to send a recorded file and to share it with your family
5. Possible to add a music file that your child likes to a lullaby list
6. Possible to listen to a selected lullaby or a mother’s/father’s lullaby continuously
7. Possible to listen to more than one sound (for instance, lullaby and white noise at the same time), or also possible to choose play time at your choice.
8. Has 4 different rattle options. (it rattles for about 3~5 seconds, if shaken left and right)
It will help improve our application. Please leave your comments after using our app, or ask if there is any specific function you would like to see.