Android Question App close with intent

Are you using Activity_Finish after you send the intent?

nop
i have tested this on my s3 and moto g
with qr code lib and camera lib

when i open a intent on my app on s3 devices it make my app close later a time
on my moto g this dont happens

i need use a code to stay runing my activity?

Normally, if you send an intent to open another app and that app finishes, it should return to the previous one (your app for example) if that doesn't happen on certain devices, then is something on that particular device that is not behaving correctly.