In this article we want to share our impressions and experiences about the development of two interactive books for children: "The Story of Miss Moppet" and "The Tale of the Kitten Tome."

To begin with, we note: the most important thing in the book is the text. That is why translation is very important for books, and for applications on the App Store: for application books, high-quality localization is very important.
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While reading the book-app, children and parents pay the most attention to interactivity, to animation, to the color and brightness of pictures, and lastly to letters. However, unlike English-speaking children, for whom developers of the whole world are trying, Russian children are not so spoiled by the presence on the App Store of interactive books in Russian with voice acting, that is, books for the youngest, where the readable text is highlighted, and you can listen to each word individually , or even a separate letter in the word! These books help to learn languages.

We decided to make interactive books in Russian with text voice acting.

Book Search

Our goal was to create as high-quality interactive book with voice acting as possible, a book in which absolutely all objects respond to pressing, so we called the series of our books immersive. Again: the main concept of our books was that in them all objects should be active, and somehow respond. The week went in search of a suitable book.

Since we wanted to make our books for children, the text in such books should be simple and it should be small. Pictures should be bright and interesting. Such books were written at the beginning of the last century by Beatrix Potter. In English, there is even the term picture book , in the definition of which Beatrix Potter made an important contribution. From the entire list of books written by a remarkable writer, for the first trial a children's fairy tale “The Story of Miss Moppet” was chosen, a charming story from the life of a cat and mouse. We like the result obtained, but not for us, but for our readers.

Now we have released a prequel of the story told in our first book - this is “The Tale of the Kitten Tom”. The book was released in September 1907, and since then has been a classic of English children's literature. A wonderful and kind tale tells about manners and how children behave. We tried, using in the second book, all the old practices, to do even better, and interesting. The new application turned out, in our opinion, even better, and we will continue the series.

Preparation of graphic material

All illustrations for the books were taken from the first publications of the beginning of the last century, they were drawn by Beatrix Potter herself. By this we, of course, saved a little time and energy for working on characters, working out scenes, and drawing illustrations. Our task was only to process and finish the pictures created at the beginning of the last century. To do this, they had to be divided into objects and draw the background and missing parts.

We came across several interactive books that used old pictures. Most often in them not all objects react to pressing, or the objects are not cut out from the background, it looks, frankly, ugly. We decided to cut the picture so that the whole background will be drawn. For each picture it was necessary to spend a lot of hard work on cutting and drawing the missing parts.

Programming

Our team includes professional programmers, but no one had any development experience for the iPhone, which was a big disadvantage.

It makes no sense to describe the study of Objective-C and Xcode, just note that it was quite interesting. Initially, after C ++, Objective-C syntax is very unusual. But in reality, there is nothing terrible, he does not suggest any new patterns, which is not surprising given that the language itself was developed in the 1980s, and has not yet undergone major changes.

An important issue is the correct choice of the Framework on which the development of the application takes place.
Cocos2d was chosen as the Framework, it is very popular, and many applications in the top are made on it. Cocos2d has excellent documentation and is open source, which is perfectly commented out and extremely transparent.

When choosing the physical C ++ engine: Box2D or C: Chipmunk , the choice was made in favor of C ++.
When programming books, we faced many problems, including the fact that the target platform is mobile and resources are limited, multithreading and multitouch were also a big problem. However, we hope that we have achieved the stability of our applications.

Text layout

The layout of the text is not very easy task, given that it should be stretched and should be dynamically imposed in the software environment. But the vector font, even on the iPhone 3, is quite readable, despite the small scale.

Writing a script that automatically stretches the text to the width is not technically difficult, but our programmers did not succeed very easily, because for the text to look beautiful, you need to have a floating distance not only between words, but also between letters. The stretched text looks as it should, and most closely matches the original.


From left to right: unstretched text; floating distance between words; floating distance between letters and words.

Words need to be divided among themselves in order to use it in the future when “acting out”, pressing and pronunciation. Note that the very animation of the word playback was carefully chosen from several options, and the most original in our opinion was chosen.

Each word needs to be associated with a sound file and the time of the word.

In general, summing up, we can say that the text takes up to 30% of the development time. But on the other hand, we make books, and it is even strange that the text takes no more than half of the time.

Voice acting

If the object in the book does not respond to a sound click, then this causes confusion and disappointment! The selection of sound is of great importance. All sounds must be in harmony with each other. They should be aligned in volume, should be no noise, crack, pleasant to the ear. Only after we added sounds did the books come to life.

The text of the book itself must be read expressively. There were no problems with the Russian voice acting, but the English one was not immediately available. Only a native speaker can read without an accent.

The first attempt at dubbing the "Miss Moppet Story" was a failure, we were promised that the girl from Zambia has a British accent and is able to read expressively. In fact, it turned out to be quite different from what was promised. We just wasted time. I had to look again. The second attempt was crowned with success, and the book was voiced by excellent British English.

In order for the application to be able to use and enjoy it, it is necessary to correctly align the volume of background music, text reading and sound effects. After trying to make a similar setup, we realized that it was necessary just to give the user the opportunity to adjust the sound in the application. Thus, to achieve the desired sound in our books, you can adjust the volume of music and sound effects separately. The overall volume is adjusted by the device button. The relative volume can be adjusted from 0% to 300%.

Results

The development of the trial application took us about 3 months. The second book, despite the fact that it is more complicated and more, we did in just a month, despite the fact that constant work was being done to improve the general basis of both applications, for example, we added strings like in “Cut the Rope”.

In the following videos you can briefly get acquainted with what we have.




Links on the App Store:
The story of Miss Moppet FULL version
The story of Miss Moppet Lite version

The Tale of a Kitten Tom FULL version
The Tale of Kitten Tome Lite version

For those wishing to familiarize themselves with the closer PROMOCODES
"The story of Miss Moppet":
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"The Tale of the Kitten Tom":
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