App lags sometimes when you passes big data as start value and your new screen(that will be opened) contains a lot of layout and blocks on screen initialisation.
Also, you should use right way to switch screens so it wouldn’t fill much ram of device and can work smoothly.
And you can use Static Variable Extension also for accessing the data across screens. Then you wouldn’t need to paas start value as you can access it with extension.
Make sure to check the clicked component IsDynamic as Gowri Sankar mentioned.