Hello.
I today bought experience boost from shop.
But i cant find it in my Stats/Adventure screen…
Did shop experience boost even appear in stats screen?
If not then this might been advice for future updates.
Just looked into this, it appears that its just a bug in the UI. The exp boost itself still works, just need to put out a patch to fix that number.
Thanks for the report!
Ok, then its bug.
I hope exp boost works, because its kill counter works…
Hope to seen fix in future updates 
It does Just verified it on my end.