Complete Guide to Monitoring iOS Game FPS with Keymob

1. Feature Overview

Keymob offers precise FPS (Frames Per Second) monitoring for iOS games, enabling real-time tracking of rendering performance and helping developers quickly pinpoint issues such as stuttering or frame drops. In this tutorial, you will learn:

  • Basic FPS Concepts and how to interpret the data
  • The differences in monitoring for standard 60Hz devices and ProMotion high-refresh devices (120Hz)
  • FPS optimization and performance tuning techniques

2. Core FPS Metrics Analysis

2.1 Basic Definition

FPS refers to the number of frames rendered per second, which directly reflects the smoothness of the visual experience.

2.2 Device Types and FPS Limits
Device Type Maximum Theoretical FPS Technical Principle
Traditional 60Hz Screen 60 FPS Fixed screen refresh rate at 60Hz
ProMotion Adaptive Device 120 FPS Dynamic adjustment between 10Hz and 120Hz
2.3 Keymob Monitoring Features
  • Traditional Devices: FPS monitoring limit is 60, matching the actual screen refresh rate
  • High Refresh Devices: Requires Stuttering Monitoring to view true variable frame rates (up to 120 FPS)

3. Step-by-Step Process

3.1 Start FPS Monitoring
  1. Connect Device: Connect the iOS device to Keymob via USB/Wi-Fi
  2. Navigation Path: In the left menu, select Performance Monitoring → Performance Charts
  3. Activate Metrics: In the top metrics dropdown, check “FPS”
    FPS Monitoring Interface
3.2 Data Collection and Analysis
  • Click Start: The tool will begin drawing the FPS curve in real time
  • Scenario Testing: Perform the following actions in the game:
    • Rapidly turn the camera view
    • Enter complex effect scenes
    • Load large resources
3.3 Key Data Interpretation
FPS Range Performance Rating User Experience Optimization Suggestions
55-60 FPS Excellent Smooth visuals with no stutter Maintain current state
45-54 FPS Good Slight frame drops, does not impact core gameplay Check GPU load/reduce overdraw
30-44 FPS Needs Optimization Noticeable stutter, impacts gameplay experience Optimize rendering pipeline/lower resolution
<30 FPS Critical Issue Severe stuttering, may lead to user drop-off Refactor core logic/implement multithreading

4. High vs Low Refresh Rate Device Monitoring Strategies

4.1 Traditional 60Hz Devices
  • Monitoring Focus:
    • Frame rate stability (Standard deviation <5 FPS)
    • Vertical sync (VSync) loss occurrences
  • Typical Issues:
    • Main thread blocking causing sudden frame rate drops
    • GPU overload leading to sustained low FPS
4.2 ProMotion High-Refresh Devices
  • Switch to Stuttering Monitoring:
    1. Uncheck FPS in the metrics dropdown
    2. Check “Stuttering Monitoring” to view true rendering frame rates (up to 120 FPS)
  • Optimization Standards:
    • Light-load scenes should maintain 80-120 FPS
    • Heavy-load scenes should not dip below 60 FPS