The developer mode on Xiaomi smartphones is a hidden control panel that gives access to dozens of additional system parameters. 9C (codename Angelica, this mode allows you to activate USB-debugging ADB, change the speed of the interface animation, simulate the secondary display and even force the inclusion 4K-But the default option is hidden, you have to unlock it through a special sequence of actions.
Many users are afraid to turn on the developer mode for fear of failures or loss of warranty. In fact, activating this menu does not affect Xiaomi warranty obligations and does not lead to automatic failures. However, carelessly changing some parameters (for example, limiting background processes or disabling MIUI Optimization) can cause lag or overheating of the device. In this article, we will discuss in detail how to safely turn on the mode, which settings are worth touching and which are better left alone.
If you plan to use the developer mode to unlock the bootloader or firmware custom software — remember that this is already beyond the standard setting and can void the warranty. For most tasks (speeding up the interface, debugging applications, testing functions), the mode is completely safe.
Why is the developer mode hidden by default?
Xiaomi, like other Android device makers, hides the developer menu for three key reasons:
1. Protection against accidental changes. Most of the settings in this section are for testing and debugging software. Inexperienced users can turn off critical services (for example, Google Play Services), which will lead to unstable smartphone operation.
2. Google Compliance: Under the Android Compatibility Definition Document (CDD), manufacturers are required to hide settings that may compromise user experience or security.
3 Performance optimization: Some options (e.g. Force GPU rendering or Disable HW overlays) can both speed up and slow down the device depending on the configuration.
On the Redmi 9C with a MediaTek Helio G35 processor and 2-3 GB of RAM, you should be especially careful about settings associated with the graphics accelerator. Incorrect parameters can cause artifacts when drawing the interface or even restarting the system.
Preparation of the smartphone before switching on the mode
Before activating the developer mode on Redmi 9C, follow a few mandatory steps:
- 📱 Check the version. MIUI. Path: Settings → The phone. → Version. MIUI. The instructions are suitable for MIUI 12/13/14, but on older versions (for example, MIUI 11) There may be minor differences in the location of menu items.
- 🔋 Charge the battery to at least 50%, which will prevent the device from suddenly shutting down during system changes.
- 📡 Connect to Wi-Fi. Some settings (e.g, OEM Unlocking requires verification via the Internet.
- 🔒 Remove the screen lock (if used) PIN/Once the developer mode is activated, the system may request a password to confirm critical actions.
If your Redmi 9C has previously been reset to factory settings, you may need to re-link your Mi Account. Without that, some options (such as USB debugging) will not be available.
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Redmi 9C with MIUI Global firmware may have a “potential security threat” alert after the developer mode is turned on, a standard warning that can be ignored unless you plan to modify system files.
Step-by-step instruction: how to turn on the developer mode
The activation algorithm is the same for all Xiaomi smartphones, but on the Redmi 9C there is one feature: after the 7th tap on the build number, a request for a password from Mi Account may appear.
- Open Settings (the gear icon on the home screen or in the application menu).
- Scroll down and select About Phone.
- Find the MIUI version line and tap it 7 times in a row. After 3-4 taps, a pop-up notification will appear, "There are 4 steps left to become a developer."
- After the 7th tap, the system will show a message: "You became a developer!". Now a new item will appear in the main Settings menu - Additional → For developers.
If the item doesn’t appear right away, try restarting the device or check if it’s hidden in the Additional section. On some versions of MIUI 14, the path may look like this: Settings → Additional → Developer Settings.
The "For Developers" item appeared in the settings|No errors in opening the menu|There are no warnings about blocking|USB-debugging is available for inclusion-->
Where to look for a developer menu after switching on?
On the Redmi 9C, the location of the item may vary depending on the version of MIUI.
| MIUI version | The path to the menu | Notes |
|---|---|---|
| MIUI 12 Global | Settings → Additional → For Developers | You may need to scroll down. |
| MIUI 13 (EEA) | Settings → About the phone → Additional → Developer parameters | Sometimes hidden under "additional settings" |
| MIUI 14 (Beta) | Settings → System → For Developers | New menu design, item brought to the upper level |
If the menu suddenly disappeared after the system update, repeat the tap procedure according to the MIUI version - sometimes resetting the settings resets the developer status.
⚠️ Note: On some firmware (for example, MIUI China Stable) Developer menus can be blocked without the Mi Account attached. If you see a message saying "This feature is disabled by the device administrator", check if the phone has a corporate governance profile (for example, via Microsoft Intune).
What settings can be changed safely?
The Redmi 9C developer menu has more than 50 options, but most of them are for Xiaomi engineers. We have selected the 5 most useful and safe options that will not harm the device:
- ⚡ Accelerating animation. Path: Debugging → Scale of animation (0.5x). Reduce the value to 0.5x Disable (Animation disabled) will make the interface visually faster.
- 🔌 USB-Debugging. Path: Debugging. → USB-It's necessary for working with ADB, Scrcpy or firmware through the Mi Flash Tool.
- 📱 Secondary display simulation. Path: Gestures → Simulate secondary display, allows you to test multitasking on screens with different resolutions.
- 🎮 Force GPU rendering. Path: Hardware acceleration → Forced. GPU-rendering. May improve performance in games, but increase battery consumption.
- 🔒 Unlocking OEM. Path: Unlocking OEM. Required to unlock the bootloader (only if you plan to install custom firmware!).
Changing the parameters of the Background process limit or Disable MIUI Optimization can lead to slowdown or overheating of the Redmi 9C. On the model with 2 GB of RAM, this is especially critical - the system will begin to aggressively close applications.
What happens if you turn off MIUI Optimization?
Frequent Mistakes and How to Avoid Them
Even when the developer mode is activated correctly, Redmi 9C users face typical problems, and here are the most common ways to solve them:
1.The developer menu is missing after the update
Reason: Reset settings when upgrading MIUI. Solution: Repeat the tap procedure on the MIUI version (7 times). If it doesn't work, check if the superuser rights have been reset (if you used root).
2. USB-debugging is off
Reason: Mi Account binding is missing or OEM Lock lock is enabled.
- Link your Mi Account to Settings → Accounts → Mi Account.
- Activate OEM Unlocking in the developer menu (you may need an internet connection).
3.The phone overheats after changing the GPU settings
Reason: Force GPU rendering or Disable HW overlays is activated on a weak Helio G35 processor.Solution: Return settings to default state or turn off forced acceleration.
⚠️ Note: If you change the settings in the menu of the developer Redmi 9C Start spontaneously restarting, immediately reset settings through Settings → System system → Resetting settings → Reset the network settings. It will return the network settings to the factory settings without losing data.
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On the Redmi 9C with 2 GB of RAM, it is strongly recommended not to limit background processes (setting the Background process limit), this will lead to constant reboots of applications and lag when multitasking.
Additional opportunities after the regime is in place
In addition to the standard features, the developer mode on Redmi 9C gives you access to hidden features that few people know about:
🔹 Error Log. Enable Debugging Record (path: Debugging) → Recording debugging information → Complete) to save system logs, which will help with crash diagnosis or support for Xiaomi.
🔹 Sensor testing. There's a Sensor Testing item on the Hardware menu that allows you to test the gyroscope, accelerometer and proximity sensor without third-party applications.
🔹 Change of change DPI Minimum width (path: Screen) → Minimum width allows you to scale up or down the interface. 9C (permit 720×1600) — 380–400 DPI.
🔹 Fake Locations: Mock Locations option → Fake location allows you to emulate GPS-coordinates through applications like Fake GPS. Useful for testing geo-dependent services.
On the Redmi 9C NFC model, a hidden NFC Card Emulation setting also appears in the developer menu, which allows you to emulate bank cards without root rights (additional software is required).