Unfortunately App has been stopped-testing it in mobile


When i export my app in mobile the first screen is working well but when i m selecting button to enter in another screen then my apps stopped automatically and saying unfortunately app has been stopped…
please tell me how to fix it…


If you need help, you need to provide more info.
Did you change package name?
Are you using clock to switch to screen?
What blocks do you have in Initialize block of the second screen?


Hello, I’m going through the same problem! :sleepy::disappointed_relieved:
See here: topic where I posted this


Hello, I was able to solve this thanks to @Hossein

You probably changed the name of the package, if that was the case check it out: here


Image below shows how to change the default package name using ApplicationPackageproperty (only visible to Scrreen1 – will globally apply to entire app). For this exercise, let’s name our app testapp and attempt to change default package-name tocom.example.testapp as shown below. Also, let’s assume your email is jdoe@gmail.com

Our simple app includes a button and clicking the button should start Screen2. The blocks to accomplish this is shown in image below. When opening another screen, we use the following convention:


  • Replace “projectname” to the “ name of the project
  • Replace “emailusername” to the “ username of your email (text before @). Also, if your username includes dot (e.g. jdoe.01@gmail.com, replace . to _ like jdoe_01)
  • Replace “screenname” to “the screen you want to open

This approach will properly work when you have built .apk. However, when using companion to test you could use approach below (thanks Boban for his input):


i have changed package name but please tell me how to fix it with my own package
please check my aiaResult.aia (239.5 KB)


You did not change the blocks to change the screen.
For example, in one of them I put emailusername.projectname.CBSE10
you would have to replace emailusername with your email user and projectname by project name.

For example, if my email was richardalves@gmail.com and the project name was LoginTest, I would have to put it like this: richardalves.LoginTest.CBSE10 (change CBSE10 by the screen name you want to go to)

Remember that the email has to be the one used to create the account.


Read this article: https://help.appybuilder.com/basic/package-name.html