Tips and tricks to fix REALME C21 problems. The product model code is RMX3201 with dual simcard slot work at 4G LTE broadband, because it is powered by MediaTek Helio G35 then 5G is not available at this phone. The first operating system is Android 10 together with Realme UI. We still not sure whether REALME C21 will get Android 11 or not.

The screen use IPS 6.5 inches HD resolution at 720 x 1600 pixels. There is small notch drop that located for 5 megapixel front camera. We can buy Cross Black or Cross Blue color. Some issues happen on REALME C21 hardware or software, therefore we will try to give more solutions, reviews and information about how to solve REALME C21 (RMX3201) troubles on community.


What are Advantages of REALME C21 Specifications and Features?

  • Network GSM 3G HSDPA or 4G LTE Dual simcard
  • LCD 6.5 inches 20:9 aspect ratio HD Resolution
  • Processor Octa-core (4×2.3 GHz Cortex-A53 & 4×1.8 GHz Cortex-A53)
  • GPU PowerVR GE8320
  • Bluetooth / GPS / Wifi
  • Memory Internal 32 GB with 3 GB RAM
  • Memory Internal 64 GB with 4 GB RAM
  • Main Camera Triple 13 MP f/2.2 + 2 MP f/2.4 + 2 MP f/2.4
  • Main Camera Features autofocus, LED flash
  • Front Camera 5 MP for video conference and selfie photography
  • Operating System Android 10
  • Battery Li-Po 5000 mAh



How to Fix or Problem Solving for Recovery REALME C21 hang or not responding or malfunctions or stuck or freezing or bricked ?

Internal storage is one important things that we have to choose for keep our installed applications. This phone has 32 GB or 64 GB internal memory options depend on the price. Of course bigger is better with more RAM as well. We can use MicroSDXC at dedicated external memory slot. There are a lot of applications that we can download from Google Play Store.

Please read many user reviews when we want to install new or not famous applications. Because some bad developers create fake apps and games that may contain viruses or malware that can make troubles if installed on our REALME C21 like become slowly or hang or stuck or broken or frozen or LCD touch screen not responsive. These kind of apps will not get Verified by Play Protect information / icon.

If we get this problem, we have to try remove temporary files and caches inside this phone, because some troubles can be solve with this steps. If we are suspected infected by virus, then please install one good antivirus like Avast or Norton, it will scan all content inside this phone. However, if the problems still happen, then we have to do hard reset to reformat our phone.

Please remember, doing hard reset or master format can make our important data removed or wiped from this phone, this is also happen with all Google account which will remove from REALME C21. We are not recommended to install APK from unknown resource for safety reasons.


How to Force Shutdown or Force Soft Reset or Reboot or Restart REALME C21 ?

REALME C21 (RMX3201) can be run with 3 GB or 4 GB RAM. Some applications may stuck or crash or corrupt when running on this phone. REALME C21 might hang or LCD touch screen not responding with any finger touch. We need to do soft reset or reboot to remove temporary files and caches. Please press and hold POWER button until REALME C21 shutdown or turn off by itself.


After this phone totally off, then we can press again POWER button to turn it ON. This process will not remove any important data, therefore we can do this process anytime we want. If our REALME C21 still can work properly, but we want to clear temporary files and caches from some applications, then please press and hold POWER button until pop-up menu appear, continue choose Shutdown / Power off / Reboot menu.


How to backup data or Contact at REALME C21 ?

REALME C21 has MicroSD simcard slot for external memory. We can backup / copy all important files and photos or videos from phone internal memory using default Android file manager, then paste it on MicroSD external memory for backup.

We can connect this phone using USB data cable to computer. After our computer finish recognizing our phone, then we can browse REALME C21 internal storage using computer file manager.

If our REALME C21 has already signed in with Google account, by default our contact will be synchronize in the background to Google server. Please make sure we check all contact at Google contact server using Internet browse to make sure backup is done.


Please note: These options bellow may not work for some devices because of firmware update version or hardware troubles or some other possibilities.

#Option 1, Hard Reset REALME C21 with software menu

  1. Turn on the REALME C21
  2. Make sure the battery is not empty
  3. Backup important data at REALME C21 because all data and applications will be erase or delete
  4. Go to Menu :  Setting 
  5. Choose Tab : General
  6. Press Backup & Reset > Restore factory setting
  7. Better you not check anything at the option if you do not want to erase data at data partition at internal memory
  8. Choose Reset phone 
  9. The REALME C21 will do the master reset process.



hard reset oppo realme c21

#Option 2, Hard Reset REALME C21 Factory Default using Hardware Secret Button Key

If we can not go to menu, or REALME C21 can not turn on or hang or stuck or frozen so we can not access the menu setting or nothing happen while touch the screen, then try to factory reset with secret button and hardware key

  1. Turn off the REALME C21
  2. Make sure the battery REALME C21 already full or more than 50%
  3. Press together and hold the Power Button + Volume Down Button
  4. If the Logo appear, then release the button, after that we will enter some menu
  5. Choose wipe data / factory reset using Volume Button, and press Power Button to Enter or OK
  6. The REALME C21 will continue master reset, wait for several minutes until REALME C21 start like new again.


How to Unlock or Fix or Bypass or Solutions for REALME C21 forgot password code or security lock screen pattern or pin (lost password)?

With triple rear camera 13 megapixel for wide + 2 megapixel for macro + 2 megapixel for DoF or Bokeh effect, we will have many private photos and videos. We also will several important applications that keep some confidential data. Please always secure our phone from unauthorized users when REALME C21 stolen or lost or away from us.

Fingerprint can be use for fast and accurate protection. It is located at back side of body. Front camera 5 megapixel can work as face unlock recognizing. We have to choose secondary protections for backup like pin or password or screen lock pattern. It will very important when REALME C21 reboot or restart, because fingerprint will not work at this moment. We have to unlock using secondary protection.

Although having security protections are very important, but some users still have some problems with this protections. They get some protection issues that can not unlock this phone or forgot security pattern / password / pin or fingerprint can not work. What should we do?

Don’t worry because we can unlock or bypass forgotten screen lock pattern or password pin protections at REALME C21 use registered Google account. Previous Google account is very important because it can use to make this phone work after force from Hard Reset or Master Format to Factory Default.

New Realme smartphone already use latest Android version already implement FRP (Factory Reset Protection). FRP is important to secure our phone when it is stolen or lost. First, we have to force hard reset or master format our REALME C21 using hardware button combination key like steps at #option 2.

After reformat finish, Android will ask for previous pin. At some Android version, we can bypass using previous installed Google account username and password after finish performing hard reset or master format. But at some other version update, we still have to type our screen lock pin or password protections. We can bypass using software at personal computer, but these steps are complicated for many users. Therefore we suggest to ask OPPO / REALME service center for bypass protections.


Is That Any Secret Code for Doing Format REALME C21 ?

There is no secret hidden code for REALME C21 to make it back to factory default. Do the options above for performing hard reset.


How to Format or Erase Phone Memory at REALME C21 ?

There are two phone memory type at REALME C21, one is internal memory and the other one is external memory. If we want to format internal memory phone then we have to do hard reset or reformat the operating system of REALME C21 as well. Please use menu setting to do hard reset or reformat using #option 1 above, but make sure to give checkbox mark at Erase Internal SD card / Internal storage. Then it will reformat the factory default operating system and remove or erase any data inside internal memory.

To reformat or wipe or erase all data at external memory, we can use menu Setting > Storage > Erase Internal Storage / SD Card. Please always make sure all data has already backup before reformat or wipe everything, because it is hard to recover formatted / wiped data at internal or external storage.


How to Make Battery of REALME C21 Stronger, Life Longer and Not Fast to Drain ?

For make it work more longer, this phone has 5000 mAh battery capacity. There are some possibilities that we can do if we want to make REALME C21 (RMX3201) battery work more longer like make LCD screen brightness as low as possible and disable all not use connections like GPS or Bluetooth or Wifi. NFC is not installed on REALME C21.