ビルド、インストール、実機でのデバッグ

# install, replacing an existing copy
adb install -r Builds/game-dev.apk

# uninstall when the signature changed
adb uninstall com.yourstudio.yourgame

# launch it without touching the phone
adb shell monkey -p com.yourstudio.yourgame 1

# copy a build to the phone's Downloads folder
adb push Builds/game-dev.apk /sdcard/Download/

# only Unity's messages — this is the one you want
adb logcat -s Unity

# clear the old log first so you only see this run
adb logcat -c && adb logcat -s Unity

# save it to a file to read carefully
adb logcat -s Unity > crash.txt

using System.Collections.Generic;
using UnityEngine;

public class ScreenLogger : MonoBehaviour
{
    private readonly List<string> lines = new List<string>();
    [SerializeField] private int maxLines = 14;

    void OnEnable()  => Application.logMessageReceived += Handle;
    void OnDisable() => Application.logMessageReceived -= Handle;

    void Handle(string message, string stack, LogType type)
    {
        lines.Add($"[{type}] {message}");
        if (lines.Count > maxLines) lines.RemoveAt(0);
    }

    void OnGUI()
    {
        GUI.skin.label.fontSize = 26;
        GUI.Label(new Rect(20, 20, Screen.width - 40, Screen.height - 40),
                  string.Join("\n", lines));
    }
}