Developer mode on Xiaomi Redmi Note 9: how to turn it on and why it is needed

Why you need a developer mode on Redmi Note 9

Developer mode in Xiaomi smartphones is a hidden settings section that allows access to advanced features of the MIUI operating system. On the Redmi Note 9 model (including Pro, Pro Max and 9T versions), this mode allows you to control parameters that are usually hidden from the average user. For example, you can enable debugging over USB to work with ADB, unlock OEM-unlocking to install custom firmware, or change the interface animation to speed up the system.

Without activating the developer mode, many technical operations can’t be performed, from simply connecting to a computer to transfer files to complex manipulations like overclocking the processor or changing the screen resolution, which is especially important for users who want to:

• 🔧 Install TWRP ornamental
• 📱 Switch to alternative firmware (e.g. LineageOS or Pixel Experience)
• 🔄 Unlock the bootloader via Fastboot
• 🎮 Optimize performance for gaming (e.g., change restrictions) CPU/GPU)

It is important to understand that not all features of the developer mode are safe. Some settings can lead to unstable device operation or even loss of warranty if you change critical settings. For example, improper setting of the Background process limit can cause constant reboots, and turning on Force GPU rendering on weak devices can cause overheating.

Step-by-step instruction: how to turn on the developer mode

Activation of developer mode on Redmi Note 9 takes less than a minute, but requires precise execution of steps.The process is the same for all versions of MIUI (12, 13, 14), including global and Chinese firmware.

1. Open the Settings app (the gear icon on the home screen or in the application menu).
2. Scroll down and select About Phone (or About Phone in English).
3. Find the MIUI version line and click on it 7 times in a row. After the first 3-4 clicks, a pop-up notification will appear, counting down: "There are 4 clicks left to become a developer."
4. After pressing 7, the system will show a message: "You became a developer!". Now a new section will appear in the main Settings menu - Additional → For developers.

If the section doesn’t appear immediately, try:

• 🔄 Reboot your phone (sometimes required to apply changes).
• 🔍 Check if the section in the search is hidden by settings (enter in the search bar "for developers").
• 📱 Make sure you don’t have a lightweight version installed. MIUI Lite (the developer mode may not be available).

Press 7 times on "Version" MIUI"|You have been told that you have become a developer!"|In the settings appeared the section "For developers"|The section is available after the reboot-->

Where is the developer mode after activation

Once activated successfully, the Developer Form can be “hidden” depending on the version of MIUI, and here are all the possible ways to access the Redmi Note 9:

If you don’t see the section, try searching by settings:

1. Open the Settings.
2. In the top line of the search, type “developer” or “developer”.
3. The system should show a direct link to the section.

⚠️ Note: Some firmware may have security policies hidden in the Developer section (e.g., on enterprise devices) that require resetting or flashing.

Main features of the developer mode on Redmi Note 9

Once you activate the developer mode, you get access to dozens of hidden settings, and we have collected the most useful and safe features that most Redmi Note 9 users will need:

• 🔌 Debugging by USB (USB Debugging – mandatory for working with ADB, Unlock the bootloader or firmware through the Mi Flash Tool.
• 🔓 Unlocking OEM (OEM unlocking - allows you to unlock the bootloader to install custom firmware. MIUI This item may not be available until you connect to your Mi Account and wait 7 days.
• 📶 Preferred network type – forced switching between 2G/3G/4G, useful in areas with unstable coating.
• 🎯 Background process limit – optimizes memory consumption, but can lead to application closure.
• 🖥️ Simulate secondary displays – useful for application developers.
• 🔄 Windows animation scale – speeding up or disabling animation to increase responsiveness.

Some functions require caution, such as:

• 🚨 Do not disable Automatic System Updates – This can lead to security vulnerabilities.
• 🔥 Don't change Minimum width (DP) Unnecessarily, it breaks the interface adaptability.
• ⚡ Don't activate Force. 4x MSAA on weak devices, this will increase the load on GPU.

💡

If you accidentally changed the setting and the phone began to work unstable, return all settings to the default state with the Reset to default button in the upper right corner of the For Developers section.

How to turn off the developer mode

If you no longer need access to advanced settings, you can deactivate the developer mode, which is useful if you're transferring the phone to another person, or if you want to return the standard interface.

Method 1: Through settings

1. Go to Settings → Additional → For developers.
2. At the top of the screen, find the switch Enable Developer Mode (or Developer Options).
3. Put him in the off position.
4. Confirm the action if the system requests a password or PIN-code.

Method 2: Resetting settings

If the first method did not work (for example, due to a system failure), reset:

1. Open Settings → System → Resetting settings.
2. Choose Reset All Settings (not to be confused with Reset to Factory, which will delete all data!).
3. Confirm action. Once you reboot, the developer mode will be disabled.

⚠️ Note: Turning off the developer mode does not reset the parameters you have changed (for example, disabled animations or limiting background processes).To return everything to factory settings, use the Reset to default button in the For Developers section before it is turned off.

Frequent problems and their solutions

When working with the developer mode on Redmi Note 9, users often encounter typical errors, and we have collected the most common ones and ways to fix them:

If none of the solutions worked, try:

• 🔄 Update the firmware to the latest version (via Settings) → Updating the system).
• 📱 Perform a reset settings (without deleting data).
• 💬 Contact Xiaomi with the model (Redmi Note 9) and version MIUI.

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If you change your settings in developer mode and your phone gets worse, the first thing you do is to return all settings to factory values with the Reset to default button, which solves the problem 90 percent of the time without resetting the data.

Security: What can and cannot be changed

Developer mode is a huge opportunity, but it also carries risks, and some of the settings can disrupt the stability of the system, break the warranty, or even disable the device, and we divided the functions into three categories by the level of danger:

✅ Safe settings (can be changed)

• 🔄 Windows/Switching Animation – Speeding Up the Interface.
• 📶 Network Selection – Forced Switching to 2G/3G/4G.
• 🔋 Do not turn off the screen while charging – useful for testing.
• 🔊 Turn off absolute volume – separate media and call management.

⚠️ Dangerous settings (change with caution)

• 🔓 OEM unlocking – unlocking the bootloader will cancel the warranty.
• 🧹 Do not save actions – disables the application log, can interfere with the work of services.
• 🔄 Background Process Limitation – Can Close Apps.

❌ Prohibited settings (do not touch!)

• 🚫 Disable HW overlays – breaks the rendering of graphics.
• 🚫 Force RTL layout – mirror interface, it is difficult to return.
• 🚫 Enable Bluetooth HCI Sniffer – can disrupt Bluetooth.

If you're not sure what the setting is, don't change it. Many of the settings in developer mode are designed to test and debug Xiaomi and aren't for the average user.

💡

Before you change critical settings, back up your data via Settings → System → Backup. This will help you recover information when you crash.

FAQ: Answers to Frequent Questions