How to make LG K51 faster – K51 lagging/running slow Fix

The first LG MetroPCS K series smartphone was LG K7. It was launched in 2017 with Snapdragon 210 processor. Since then, every Metro LG K Series device came with a Snapdragon CPU, except for the latest LG K51 cellphone which is equipped with an entry-level Mediatek Helio P22 processor.

LG K51 feels slower than its predecessor K40. K40 uses a more powerful Snapdragon SDM450 processor.

If your LG K51 is running slow there are a few sureshot ways to boost its performance. Let’s see how to make your K51 faster –

How to make LG K51 faster – LG K51 lagging/running slow – How to Fix


1. Reduce the Animation Scale via Developer Options

The animation scale settings are found in Developer options.

On LG K51 the Developer Mode is hidden. You need to tap the “Build Number” 7 times to enable it.

Please follow the below link to turn on the Developer Option on your K51 –

LG K51 Developer options – How to enable

Now, Open the Settings app and click on “System”.




Choose “Developer options” and scroll down to the bottom.




Look for “Window Animation Scale” and click on it.

Right now the Animation scale is set to 1x. To speed up your K51 you can either reduce it to 0.5x or turn it off completely.



The next one is the “Transition Animation Scale”.

Do the same with this. Either choose the “Animation off” option or “Animation scale 0.5x”.



The last one is the “Animator duration scale”.

Reduce the animator scale speed to 0.5x or disable it.


I’ve turned off all the 3 animation scales. Give it a try and then adjust it according to your preference.


2. Do smart cleaning to free up RAM and ROM on your K51

LG K51 has a smart cleaning tool to give a quick boost in speed.

It optimizes the phone by clearing the cached data and closing the unused apps.

For smart cleaning, please open the Settings app and select “Extensions”.



Click on “Smart Cleaning” and then tap “Optimize phone”.




It’s now optimizing the phone by deleting unnecessary files and stopping unused apps.



3. Empty your LG K51 Trash Can/Bin to speed up your phone

The 3rd step to fix the performance issue on your K51 is by freeing up the internal memory.

K51 has a very limited internal storage space. When you delete the photos and videos they are accumulated in the trash folder. It’s like the recycle bin on your computer.

You can free up the internal memory by emptying the LG K51 trash can.

Open the “Gallery app” and hit the “3 dots icon” at the top-right corner.



When the dropdown appears, select “Trash” as shown above.

Hit the “trash can icon” to permanently delete the files stored in this folder.




Tap “Delete album” to confirm your action.

There is one more way to free up the internal storage space. You can use the LG K51 adoptable storage feature to partition your SD card as internal storage. This way you can move apps to the SD card and make it the default storage space for apps and games.

Let’s see how to do this as follows –




4. Move apps to the SD card and use the SD card as internal storage

I’ve partitioned the SD card on my LG K51.

The total device storage space is now increased from 32GB to 40GB. I’ve partitioned my 8GB micro SD card as internal storage and moved all the data from internal memory to the SD card.

Please follow the below link to learn how to do this –

How to move apps to SD card on LG K51


5. Downgrade the LG K51 firmware from Android 11 to Android 10



Is your LG K51 slowed down after the Android 11 upgrade? If you feel the phone was faster when running on Android 10, you can revert to the older firmware.

You can downgrade the LG K51 MetroPCS/T-Mobile software from Android 11 to Android 10 using the LGUP flash tool.

You can see I’ve flashed the K500mm10r Android 10 kdz file to downgrade from Android 11 k500mm20f firmware.

Please follow the below link to learn the detailed procedure –

LG K51 Firmware Download & Downgrade – Android 11 to Android 10 

Were you able to speed up your K51 after using the above tips? Please share your experience in the comment section below.



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