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Android Mobile Device Management

Enforce filtering and device settings by managing an Android device

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Tech Lockdown Team
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Updated March 30, 2024

Android smartphones have limited ways that you can block unwanted content and restrict easy bypass of those content restrictions.

However, it's possible to configure a fully managed Android smartphone, which gives you much more control over content blocking and bypass prevention.

Businesses will often use Mobile Device Managers (MDM) to completely control smartphones that they issue to employees for business purposes

As a result, Mobile Device Managers unlock powerful capabilities that allow you to block unwanted content and prevent bypass much more effectively.

The best part is that once a setting is enforced with a Mobile Device Manager, these settings cannot be changed from the device itself. The settings can only be changed in the MDM dashboard.

You don't need to be a business to access Mobile Device Management capabilities. In fact, you can get access to Device Management for free! 

Capability Overview

Here are some capabilities that you unlock using a mobile device manager:

Remote Management

With an MDM, you can remotely configure a fully managed device. This means that you can make policy changes and those changes will be automatically synced with the Android device you are managing. You don't need physical access to the device to make changes.

Prevent App Uninstall and Remotely Install Apps

When you use the "silent installation mode," you can remotely install an app on a device. This remotely installed app can't be deleted by the user on the device. It has to be uninstalled using the MDM.

This is a powerful feature when combined with a DNS Filtering application or a content blocking application.

Content Filtering

Enforce built-in browser content filtering to block Adult and malicious content. You can even set up a restrictive "allow-only" mode where all websites in the browser are blocked by default unless you specifically added them to the allow list.

App Management

Create an app policy such that a user cannot download apps that haven't been explicitly approved. 

Alternatively, you can allow all apps other than the ones you explicitly block.

Remote Lock and Wipe

In case of a lost or stolen device, adults can remotely lock or wipe their smartphones to safeguard personal data and prevent unauthorized access. This feature provides an extra layer of security and peace of mind.

Geolocation Tracking

Mobile device managers often offer location tracking capabilities, allowing adults to keep tabs on the whereabouts of their smartphones. This feature can be useful in case of misplaced devices or for ensuring the safety of family members.

Before you get started

Important

For full control over a device, you need to hard reset the phone. A hard reset will delete everything on the device, but you shouldn't need to reactivate your phone's service.

Get started with Manage Engine

This setup guide uses the Mobile Device Manager called Manage Engine. The free tier is perfect for home use. The interface is a bit rough, but usable.

Signup for ManageEngine

Note

When the 30 day free trial expires, you do not need to pay. Your account will transfer to the free tier and the free tier is limited to 50 devices but has the same functionality. 

Setup Video

The below video shows the entire process from start to finish with some explanations of some steps. 

Outdated content

This video was created several years ago, so the Manage Engine interface has changed since then. This is mostly useful if you are confused about the enrollment process.

Use this video as a supplement to the rest of the guide.

(1) Enroll Device

This section explains how you connect your Android device to a Mobile Device Manager. 

(2) Configure Profile

A mobile device manager uses profiles to set device restrictions and enforce settings. 

Create Profile

Restrictions (Security)

Restore Factory Settings

This setting is useful for some people, who might go to great lengths to access an unfiltered device. Keep in mind that you can still reset the device using the MDM.

Lock Screen Notification Preferences

Consider enforcing either option: Hide Sensitive Content or Don't show notifications at all. This is useful if you are trying to reduce your smartphone usage and don't want to be constantly interrupted by app notifications. Enforcing this setting means that you don't have to manually customize this option. 

Safe Mode

Some bypass methods utilize the device's safe mode. I recommend disabling safe mode.

Developer Mode

Similar to safe mode, developer mode can be used to bypass some restrictions. However, these methods are more difficult than safe mode. Consider disabling this.

Restrictions (Applications)

Users can install unapproved apps

This is a powerful feature because it allows you to blocklist any app (excluding system apps) that aren't specifically approved in your MDM. Consider checking this option if you need a much more restrictive device setup.

Uninstalling apps

Preventing app uninstall is useful but not required. If you want to enforce the use of an application and prevent uninstalling, you'll just distribute the app with the MDM. However, you might find it useful to prevent uninstalling apps.

Stop system apps

I recommend disabling this option so that the users can't force-stop certain apps.

Global App Permission Policy

Consider setting this to auto deny.

Browser Restrictions

Android Browser

Restricting the android browser will remove the ability to use any kind of internet browser on the android device. This setup is incredibly restrictive, but useful for people who want a "dumb phone" without sacrificing GPS and music players.

Network and Roaming

Wi-Fi

You could potentially restrict the device so that it can only connect to an approved Wifi connection, such as your home network, which uses a content filter. If you choose this option, you must set Wi-Fi to Always on, otherwise, the user can bypass this restriction by disabling Wi-Fi and browsing on the phone's roaming connection (3g, 4g, 5g internet).

Allow users to configure VPN

This setting should be disabled since a VPN can be used to bypass DNS Filtering.

Kiosk Mode

Enabling Kiosk mode gives you access to even more device restrictions. 

You can enforce Kiosk mode. Here's my phone running in kiosk mode in Multi App Mode:

Consider blocking access to the following Android features by not including them in the Allowed Apps list:

  1. General Settings app
  2. Web Browsers
  3. Google Play store or Android App Store

Web Content Filter

Allowlist - Allow-only mode

This is also known as "default deny" and will block access to everything other than the URLs you specify here. This is the most restrictive content filtering setup, so use this with caution.

Blocklist - Block specific URLs

This is a more common content filtering approach. 

(3) Distribute profile to device

Update the device to use the restrictions you specified in the profile you created.

If you plan to manage multiple devices that use the same device restrictions, I recommend creating a device group.

Creating a device group simplifies the process of distributing apps and profiles to multiple devices at the same time.

The profile should automatically sync to the devices that are associated with that group. It might take a few minutes to sync.

(4) Managed Google Play

Configure managed Google play so that you can install apps on your device using the MDM. This will allow you to force app configurations and prevent uninstall while also preventing certain apps from being installed.

How to

Prevent App Uninstall

Enforce apps on Android / Prevent deleting app on Android

Distribute an app to all devices associated with a group. This is a great way to enforce app settings, prevent app uninstall, and also automatically install an app on all devices enrolled in your MDM (and associated with your group).

Block Apps

Blacklist apps / Blocklist apps / App Blocking techniques

Blocking an app using the MDM will uninstall the app from the device if it was previously installed and prevent it from being installed in the future.

Frequently Asked Questions

Prevent deleting an app

You can configure your Profile to disable allowing the user to uninstall apps on the device in Your Profile > Restrictions > Applications > set Uninstalling Apps to Restrict.

Alternatively, you can prevent app uninstall on a case-by-case basis by distributing the app with your MDM and modifying the app's permissions to block app uninstallation. In Device Mgmt > App Repository, add the app that you want to enforce. Then, select the app and go to the permissions tab > advanced permissions. Then, set Block App Uninstallation to Allow. Distribute the app to the devices in your group.

Block VPNs, Proxies, or other apps that configure DNS?

How to block VPNs and proxies on Android.

There are a few approaches to doing this. First, make sure that your profile restrictions > Network and Roaming has Allow users to configure VPN set to No

Next, consider updating your profile to only allow a user to install an app that has been explicitly approved via your MDM. This will blocklist all apps by default and only allow the user to select from apps that are on your approved list. You can update your approved list by adding apps to your app repository in Inventory > Apps. Then, update your profile > restrictions > Applications and set User can install unapproved apps to Restrict.

You can also manually block each one of these kinds of apps, but this solution can be time-consuming and not comprehensive. However, it will significantly slow someone down because they won't know which apps are blocked until they try to install the app and it is automatically deleted. If you are managing a device for another person (like a child), they might assume that all VPNs/DNS apps are blocked and won't attempt to find an unblocked app.

You can also set an always-on VPN in your profile > VPN > check Always on VPN after configuring VPN settings.

Alternatively, you can configure Kiosk mode.

What are the most restrictive setups?

The recommended options are indicated in the above profile configuration section. However, here are some specific call-outs:

Kiosk mode

Kiosk mode lets you customize and limit the use of the phone to a small subset of features. For example, In Multi-App mode, the user only has access to approved apps even if unapproved apps are installed on the device previously. The apps aren't deleted, but they can't be opened.

You can also use Kiosk mode to enable Single App Mode, which lets you enforce the usage of a Kiosk app or any other app. The user can't close or switch out of the app specified in Single App Mode. This is useful when combined with a parental control kiosk app.

You can also further restrict WiFi and Network access with kiosk mode. In my opinion, the main use case for Kiosk mode is combining it with a parental control kiosk app. Otherwise, I don't think it's a viable option for most people. 

Restricting/Enforcing WiFi

Restrict Wifi to only your home network. This requires that you update your MDM Profile > WiFi to include your Wifi network name in the Wi-Fi SSID field, the security type specified (usually this is WPA/WPA2) with the Wifi password entered. Then, in your profile > Restrictions > Network and Roaming, you set AWiFi:Always On and Connect to Wi-Fi if distributed via MDM:Yes

Disabling the android browser

You can completely disable the ability to use internet browsers on your device. This is a great alternative to a dumb phone because you can still use apps like GPS/Maps, Spotify, etc., but you don't have to worry about plugging all the browsing loopholes.

Web Content Filter

Enabling the "allowlist" mode in the web content filter will restrict access to all URLs other than the ones you specify. This is also called a "default-deny" approach where you can't visit a URL unless it is specifically allowed.