Instabug automatically captures the time it takes for any given screen to load. This covers the time for any View Controller between viewDidLoad and viewDidAppear which includes the following lifecycle methods:

• viewDidLoad
• viewWillAppear
• viewWillLayoutSubviews
• viewDidLayoutSubviews
• viewDidAppear

End Screen Loading

You can also define custom points in each View Controller to manually inform the SDK that screen loading has ended.

APM.endScreenLoading(for viewController: self) // self here is a reference to a UIViewController

[IBGAPM endScreenLoadingForViewController: self]; // self here is a reference to a UIViewController

Screen Loading Apdex

Instabug calculates an Apdex score for your app traces as a way of measuring their performance. An Apdex score ranges between 0 and 1; the higher the value, the better:

• Apdex score ≥ 0.94 equates to Excellent performance.
• Apdex score ≥ 0.85 and < 0.94 equates to Good performance.
• Apdex score ≥ 0.7 and < 0.85 equates to Fair performance.
• Apdex score ≥ 0.5 and < 0.7 equates to Poor performance.
• Apdex score < 0.5 is considered Unacceptable.

How Is the Screen Loading Apdex Calculated?

When an app trace occurrence is collected, it is flagged based on a pre-defined target (T). An app trace occurrence is considered:

• Satisfying: if its duration ≤ T
• Tolerable: if its duration > T and ≤ 4T
• Frustrating: if its duration > 4T

Then based on the bucketing explained above, the Apdex score is calculated as follows:

• Total occurrences = Satisfying occurrences + Tolerable occurrences + Frustrating occurrences
• Apdex score = (Satisfying occurrences + 0.5 * Tolerable occurrences) / Total occurrences

How Can You Control a Specific Screen's Target?

By default, the target is set to 0.25 seconds, however, you can easily change this number from your dashboard by clicking on your current threshold in the Apdex section.

Disabling/Enabling Screen Loading Tracking

If APM is enabled, our SDK starts collecting data about your screen loading time by default. If needed, you can always toggle this on and off by updating the relevant flag after the SDK is initialized:

APM.screenLoadingEnabled = false

IBGAPM.screenLoadingEnabled = NO;