Application slows down too much while using and turns off

Application slows down too much while using and turns off. Any idea why?
Thanks,

Hi Unver, can you give me some more details? Are you talking about the build version or is it slow in the preview app? What does your application do?

Hi, I use recycle view to show list of photos. At start It works very fast. After a while lists are getting slower end at the end closing the app in both preview and the build. I checked debugger. It says “Failed to get size for image” before close or stuck…
Is that clear? I can share my app id 97500.
Thanks a lot.
Ünver