thank you @jjazeix , I'll make the changes & improvements you mentioned.

@rahulyadav & @jjazeix thanks for your suggestions, I will try to remove these bugs.
Also, in order to test this activity in android , what will be the steps to convert this into an apk file ??

thanks @rahulyadav for your feedback.I'll make the changes after discussing them with Johnny & emmanuel.
@jjazeix & @echarruau , it would be great if you could also suggest some changes & modifications.

Thanks for the feedback.
I will include the changes you mentioned.

Same problem on IPAD. In native Android development, this problem is related to activity life cycle. When screen orientation changes the activity is restarted and if some ongoing threads are performing some task during that instance then the app crashes or freezes.
link 1
usually the solution is to make some changes on App manifest file.
I tried to find the source code of the app, but was not able to figure it out.
Maybe someone can help with this issue.

Can I do this task ?
some questions :-
1.) The Screenshots should be in which format (svg or jpeg)??
2.) The link of repo is "https://github.com/gcompris/GCompris-site" , under it there is a 'screenshots' section , so I have to make another section named 'qtscreenshots' inside it or outside it.??

No , I have not tested the JB Butet version. According to you should I create an activity from scratch or some modifications in JB Butet version ??

Hi , if this task is open can I work on this Activity??

Hi , if this task is open can I work on this Activity??

no problem sir . I will try to contribute in some another activity . Can you please share some of the tasks that are open & need some work , I can work on them.
Thanks.

Idea is really nice .Can I take this Activity if its still open ??