About this app

Why wait 'til you can read? Learn programming now!

Turtle likes drawing. He makes the most beautiful drawings with his tail: step, rotate, change color and make big or small steps. But sometimes Turtle does not remember how he made those beautiful drawings.

Fortunately, his friends like to help Turtle. When they go to school (long click button), Monkey, Elephant, Owl, Hamster and Mouse will remember all the buttons used. When they leave school (long click button again), you will see that they earned a certificate. They now remember the buttons and with a click on Monkey, Elephant, Owl, Hamster or Mouse, they repeat exactly what they have learned! They always do the same, but if you start in a different place, with a different color or with smaller or larger step size, the picture may look different.

The friends love to help each other. As example, Elephant can ask Monkey or Owl, or Hamster or Mouse to repeat what they have learned.

Sometimes you want to do something more than once. The dice show how many times: 1, 2, 3, 4, 5, 6, 12, 18, 24, 30 or even 36 times. Monkey, Elephant, Owl, Hamster and Mouse learn in school how often they have to repeat something. In this way, they can create very complex pictures!

Turtle saves the most beautiful pictures in the album. He likes flipping the album (swipe left or right). The album also holds the certificates, so Monkey, Elephant, Owl, Hamster and Mouse remember what they learned when the image from the album was drawn. That way you draw the same picture again, or a somewhat different one.

Sometimes Turtle gets lost; he does not know how to get back. Then his friends shout loudly: "Come to the center!" In that way, Turtle finds his way back.


TURTLE LANGUAGE REFERENCE MANUAL (text for adults)
"Turtle and his friends" is designed for toddlers (starting at about 4 years) ands children up to around 10 years.
"Turtle and his friends" uses the principles of 'turtle graphics' of the Logo programming language, but without written language. Monkey, Elephant, Owl, Hamster and Mouse are the 'procedures' in the 'language'. The 'procedures' can call each other (nested procedures). Going to school is programming a procedure. The dice are the loop control structure.

- The school is very small. Only one friend can go to school at a time.
- A friend who is in school, cannot be asked to draw.
- When Turtle is busy drawing, the buttons to step, rotate, change colors or change the step size can be still be used. That changes the picture as it is drawn and sometimes makes a total mess. My grandchildren find that very funny!
- If the screen shows a picture from the album (red color on the album button), the picture can be deleted from the album by a long click on the clear button (the rake).

The picture and certificate album is stored locally and is available next time you start the app. The app does not collect or store any other information.

'Turtle and his friends' was been designed for tablets. It works on my phone, but then the buttons are very small and the drawing speed is really low.
'Turtle and his friends' was built with App Inventor, developed by Google and now managed by MIT. App Inventor gives some limitations:
- Despite optimizations, the speed of drawing for complex pictures could be better. On the other hand, understanding of programming is enhanced if the children see the drawings being built up.
- At installation, the app requests approval to access to the Internet. 'Turtle and his friends' does not access the internet and can be used without internet access active.

New features

In some Android versions, the pictures stored in the book were only partly reproduced. Corrected

App Permissions

Allows applications to open network sockets.
Allows access to the vibrator.
Allows applications to access information about networks.
Allows applications to access information about Wi-Fi networks.
Allows an application to write to external storage.
Allows an application to read from external storage.