This is a weird issue, I am not sure this is an issue even, since I am reporting it only for this app and nowhere else.
Try scrolling, scaling, zooming in/out on the stacked bar chart. It will eventually start lagging.
Basically the app uses so much CPU that the device becomes heated in seconds. Let me explain.
At some point I noticed that the charts started lagging, i thought it was a memory leak somewhere or smth. Tried to record it.
Then realised, that enabling recording itself makes the app lag.
Going into power saving mode - makes the app lag even more.
I have not seen such behavior in other apps, although this is one of the last i am testing now. Thats why i think its an issue.
In general, i think that the app throttles all the CPU so if you would have some music app in the background or use anything else on the phone besides this app the lags would be noticeable.
Maybe the video helps to see the issue.