Owners of Xiaomi, Redmi and POCO smartphones often notice a component called “Handbook” or “Mi Credit” in the installed application list. Its appearance in the list of processes can raise questions, especially if the user is not familiar with the ecosystem of the Chinese manufacturer. Many become worried about security, believing that it is a virus or spyware that collects personal data.
In fact, it's a standard system service integrated into the MIUI shell and the new HyperOS, designed to provide quick access to contacts, calls, messaging history and financial features depending on the region of use, and understanding its purpose will help avoid unnecessary actions to remove or block important system processes.
In this article, we will examine the functionality of this application in detail, find out why it consumes resources and whether it can be turned off without consequences, and you will learn how the global version of firmware differs from the Chinese version in the context of the service.
What is a system application Directory in MIUI
The Handbook app (often called Yellow Pages or Mi Credit in English) is an integral part of the smartphone’s software shell, and its primary function is to identify incoming numbers and sort contacts, and unlike a standard phone book, it can recognize delivery, taxi, bank, and telemarketer numbers if the database is available in your area.
The functionality of the component depends on which version of the operating system is installed on the device. In Chinese firmware, this module is closely integrated with local payment systems and lending services. For users from Russia and CIS countries, the functionality is often reduced to the basic number detector or completely hidden, but the process remains in the system for correct operation of calls.
It's important to understand that the system directory is not third-party software, it has deep access rights to the contact database and the call log, so that when you call in, the system can instantly check the number internally and display not just a name, but, for example, the name of the organization or type of service.
Users often confuse this application with a regular contact list, but technically they are different processes: one stores data (Contacts) and the other (Directory)./Yellow Pages) is engaged in their verification and advanced classification. Deleting one can lead to incorrect display of information in the other.
The main functions and capabilities of the service
Despite its apparent simplicity, the app has a wide range of communication tools, primarily a clever sorting of incoming calls, and algorithms analyze a number and assign it a category, allowing the user to immediately know who is calling, even if the number is not in the notebook.
The second important function is message integration: the directory can automatically group SMS from banks, delivery services and service centers into separate folders, separating them from personal correspondence, which helps keep messages in order and find the necessary confirmation or order notification codes faster.
In some firmware versions, especially those for the Asian market, the app also acts as a digital wallet, which allows you to pay bills, transfer money, and even borrow microloans, but in global versions of the Global ROM, these features are usually not active or replaced with regional counterparts.
It's worth noting that you can use business cards to create digital profiles that you can share through your business cards. QR-code NFC. This makes networking and contact sharing in a business environment easier without having to manually type numbers.
Technical features and resource consumption
Like any background service, the Directory consumes RAM and battery power, albeit in small amounts. It must be constantly active to respond instantly to an incoming call. If the process is killed by the energy saving system, the number determination may not work, and you will see just numbers.
The main load on the processor occurs when the database is synchronized or spam lists are updated. In normal standby mode, resource consumption is minimal. However, users sometimes notice that the Reference application or related processes (com.android.yellowpages) can accumulate cache.
Cache files contain temporary data, such as caller images, company logos, business cards, and over time, this data can grow to several hundred megabytes, which is especially critical for devices with a small amount of internal memory.
⚠️ Warning: Forced stop of the "Directory" process through application settings may cause incoming calls to be displayed without a name. ID, a the application "Phone" may start to work unstable or fly out.
Also worth mentioning is permission to access geolocation, which sometimes requests location access to offer relevant services nearby (such as payment points or partner offices), which is often disabled in global firmware, but a permission request may pop up.
Instructions: How to set up and use the directory
For most users, the default settings are optimal, but if you want to improve call identification or limit functionality, you can change the settings manually.
First, you need to log into the Phone app. In the upper right corner, you have a three-dot menu or a setup gear. Go there, find a section that might be called Number Definer, Yellow Pages, or Directory Services.
In this menu, you can turn on or off downloading updates to the number database, allow advertising to be displayed (in some regions), or activate smart SMS sorting. There is also a feature called “spam calls” that uses a cloud database.
☑️ Setting up the number determinant
If you're using a corporate version of a smartphone or a specific build, the path may be different, so try to find settings through the general Settings section → Apps → All Apps → Directory. Access rights and notification management are available here.
Problems, mistakes and ways of solving them
Despite the stability of the work, users can encounter errors, the most common problem is that the number definition stops working or the directory stops updating, often due to network connection problems or blocking update servers in a particular region.
Another common case is that the Handbook app is constantly hanging in Task Manager and warming the phone, which may indicate a bache in a particular version of MIUI or a conflict with third-party software installed for calls, in which case the data cleanup helps.
To clean up, go to Settings → Apps → All apps, find the "Handbook" (or Yellow Pages) list. Click "Memory" and then select "Clean" (not to be confused with "Clean All" if you want to save settings, but it's better to clean everything for a complete reset).
| Type of problem | Probable cause | Method of decision |
|---|---|---|
| No number is specified. | Internet or server down | Check the network, turn on Wi-Fi |
| High battery consumption | The suspended synchronization process | Cleaning the app cache |
| No database updates | Regional restrictions | Changing the region in the phone settings |
| Advertisements pop up | Setting up MIUI recommendations | Disable MSA and recommendations |
In rare cases, changing the region in smartphone settings helps, for example, switching to the region of Singapore or India can activate other update servers where the database works better.
Security: Should the application be removed?
Removing system components is always a hot topic, and the desire to make room and remove the extra is clear, and the Handbook is closely related to the telephony module, and its complete removal (through ADB or root rights) can cause the phone to stop accepting calls or to go into an endless reboot when trying to dial.
Is it a virus? No. It's a legitimate app from the system's developer. However, it collects metadata about calls to improve the database (anonymously, according to Xiaomi's privacy policy). For paranoid users, this can be a drawback.
If you don't use the determinant features and prefer third-party applications like TrueCaller or GetContact, you can try to disable the system directory. But you can't do this with standard means, because the "Disable" button will be inactive.
⚠️ Note: Removing system packages through ADB Removing the wrong component (e.g. com.miui.yellowpage) can disrupt the entire call system.
The safer way is not to delete, but to limit. In the battery settings, limit background activity, deny access to geolocation and microphone (if you have such a request), and the application will consume a minimum of resources without interfering with the main function of calls.
Differences in Global and Chinese Firmware
The difference between the software versions is enormous. In Chinese firmware (CN ROM), the Handbook is a powerful combine of search, payment, credit and navigation functions, designed for local services (WeChat, Alipay) and is unparalleled in our understanding.
Global ROMs (EEA) have cut out or replaced this feature with a basic number detector running through local databases or Google servers, so users in Europe and Russia see only a pale shadow of the functionality available in China.
Attempting to install the Chinese version of the Guide on global firmware often leads to compatibility errors. the application may simply not start or require the installation of additional frameworks, which creates an unnecessary burden on the system.
If you've reflashed your phone from the Chinese version to the global version, the remnants of the Chinese directory can sometimes stay in the system, and it's best to delete them through Recovery or when you flash it with Wipe Data to avoid conflicts.