Your question is Diagnose and Optimize Slow Apps. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
How would you diagnose why an app is running slowly and optimize it? Walk through how you would find the bottleneck, measure improvement, and decide which code-level changes to make first.