Buyer / consumer
DevCheck AI
Trust Score + AI analysis + IP reputation + shareable device certificate. Check a phone before you pay for it. 7 MB.
Features →
Third sister app · engineer edition
Every frame,
measured on the device.
PerfMonitor is a ~7 MB non-root Android tool for game and performance engineers. It reads the real SurfaceFlinger per-frame timestamps, plus CPU / GPU / DDR frequency and load, power, thermals, memory — surfaces them as a floating overlay while you play, and exports CSV and XLSX reports with methodology notes baked in. No host, no wires.
- APK size
- ~7 MB
- Root needed
- No
- Live curves
- 8
- Android
- 8.0+
Which app do you want?
Three apps in the DevCheck family, three different jobs. Same team, same 84K-device reference database behind the scenes.
Engineer · read-only
DeviceInfo Viewer
15-dimension raw dump of everything Android will surface. For privacy audits and anti-fraud research. Tiny APK.
Viewer →Engineer · performance
PerfMonitor (this one)
Live floating overlay: real per-frame FPS, jank, CPU / GPU / DDR, power, thermals. CSV + XLSX exports with methodology attached. 7 MB.
What it measures ↓What it actually measures
Numbers with defined semantics — every metric on the overlay has the same definition in the export report.
🎯
Real per-frame FPS
Reads SurfaceFlinger's per-frame present timestamps directly. Not estimated, not sampled — the actual frame time the compositor logged.
⚠️
Jank & BigJank the way engineers count them
A frame is jank when its render time exceeds 2× the trailing 3-frame average AND >83.33ms. BigJank crosses 125ms. Idle stretches (menus, loaders) are excluded from stats — they don't get miscounted as stutter.
📉
Worst-1% FPS — two ways, side by side
Mean of the worst 1% frame intervals (captures peak pain) and the 1% percentile frame (unaffected by extreme spikes, reflects overall level). You get both, always.
🌡️
CPU / GPU / DDR frequency + load
Per-cluster CPU frequency and per-core utilisation. GPU frequency + load (Qualcomm kgsl / MediaTek gpufreqv2 auto-detected). DDR memory bus frequency (Qualcomm / MediaTek / Xring branches).
🔋
Power & thermals
Live current × voltage → instantaneous power draw, plus per-frame average energy. Battery temperature and memory usage. Values a SoC doesn't expose show as `-` and don't fake an empty chart.
🪟
Three-tier floating overlay
Tap to cycle: Compact (fps + temp only) → Slim (4 rows + FPS curve) → Detailed (all metrics + 8 independent curves). Four opacity levels; the highest strips the backdrop so it doesn't cover the game.
📊
Live curves for everything
FPS, CPU cluster frequencies, per-core utilisation, GPU freq/load, DDR freq, power, battery temp — each a separately-coloured line. Missing signals just don't render.
🎬
One-tap Perfetto trace
Capture a 10-second system-level Perfetto trace straight to disk. No adb, no host tools — just the button in the overlay.
Three overlay tiers, tap to cycle
Compact for a passing glance, Slim for the smoke test, Detailed when you need every curve at once. The control bar pins to the top so it doesn't scroll away with the content; four opacity levels, highest strips the backdrop so nothing covers the game.
- Compact — fps + temperature, minimum footprint
- Slim — 4 rows + a single FPS trace
- Detailed — every metric, 8 independent curves
- Auto-follow foreground app or lock to a specific one
Exports you can defend in a review
Every metric ships with the exact rule used to compute it. No mystery numbers when you paste a stat into a bug report.
CSV
Three sections — Session / Aggregate / Raw. Every metric carries its unit and a methodology note. UTF-8 with BOM so Excel opens it clean.
XLSX
Aggregate cells are live Excel formulas, not baked numbers. You can re-run the math or change the aggregation rule in the sheet itself.
Files land in Download/PerfMonitor/,
visible to any file manager, and shareable via the system share sheet.
How it reads what a regular app can't
The metrics live in places the untrusted_app
SELinux domain has no access to: SurfaceFlinger frame timestamps, /proc/stat,
cpufreq / kgsl sysfs nodes. PerfMonitor ships a built-in Shizuku server
to lift itself to adb-shell privileges — no third-party manager app needed, and no root required.
1. On-device wireless debugging (Android 11+, recommended)
Built-in ADB pairing client. Enter the pairing code from Developer Options right in the app. Whole flow happens on the phone — no computer required.
2. Root
Rooted devices launch the server directly, and get extra metrics from nodes only readable in the root domain.
Without activation, the app degrades gracefully — power, temperature, memory and other pure-SDK metrics still work.
Permissions & privacy
| SYSTEM_ALERT_WINDOW | Show the live overlay on top of the game |
| FOREGROUND_SERVICE | Keep collecting while the game is foregrounded |
| QUERY_ALL_PACKAGES | Populate the target-app picker |
| POST_NOTIFICATIONS | Persistent notification for the foreground service |
Nothing is uploaded, ever. All collection, statistics and file writing happen on-device. Exports live in local storage under your control.
Download & install
perfmonitor-v0.1.0-demo.apk
v0.1.0-demo · arm64-v8a ·
com.android.perfmonitorSHA-256
933442b6ef7d348d08025b568a06ba54488a90e8aec5191d792be834487fd4b4
Verify integrity after download:
shasum -a 256 perfmonitor-v0.1.0-demo.apk
# should output the SHA-256 above, exactlyQuick start
- Install the APK and open PerfMonitor.
- Tap Grant Shizuku → follow the on-screen guide → One-tap wireless-debug activation. Enable Wireless debugging in Developer Options, tap Pair with pairing code, keep the dialog open, and enter the 6-digit code in the app. Pairing succeeds → server autoruns.
- Back on the main screen, the status should read Authorised / backend SHIZUKU.
- Pick a target app (search supported), or turn on Follow foreground app.
- Tap Start overlay, switch to the game, play.
- When done, tap Export CSV / XLSX.
Known limits
- arm64-v8a only. 32-bit devices are not supported.
- SurfaceFlinger's frame buffer is fixed at 128 frames — sustained >~128 fps leaves gaps (they aren't miscounted as stutter, but the stats for that window are incomplete).
- GPU / DDR sysfs nodes vary by SoC and ROM. Uncovered platforms show `-` for the missing metrics.
- Some ROMs (MIUI / HyperOS) reset overlay permission after a reinstall — re-grant it in the security centre.
- Apps protected by FLAG_SECURE can't be screenshotted (does not affect metric collection).
- The bundled service runs as a separate process — uninstalling the app doesn't stop it. Reinstall → activate once more.
Measure it, don't guess.
7 MB, non-root, no host tools. On-device wireless-debug pairing, live overlay, CSV + XLSX exports with methodology attached.
