How to revert to the previous version of Android: You have always applied the Android updates proposed by your manufacturer without asking yourself too many questions but, this time, something went wrong: following the last update, the device started behaving strangely , causing you difficulties and inconvenience during its use. To overcome this problem, you would like to “cancel” the update made and return Android to its previous state but, after having looked at the device settings for a long time, you could not find a suitable function for your case.
If I have described your problem perfectly, know that this is just the place to start! During this tutorial, in fact, it will be my care to explain to you how to return to the previous version of Android by applying a “customized” operating system to your device. As you will soon discover, however, acting in this way is far from risk-free : a small distraction error or, even worse, a file that is not suitable for your device is enough to make it unstable or even break it. altogether.
For this reason, I invite you to seriously consider the consequences to which the Android downgrade could lead you and to act only if you know exactly what you are going to do: I have warned you and I do not take any responsibility for any damage done to your device, either clear!
Before going ahead and explaining, in practice, how to return to the previous version of Android , let me give you some more specific information about the procedure you are about to perform. First of all, I consider it a duty to make you aware of some terms strictly related to the procedures that I will talk about in the course of this guide.
- Bootloader – is the program that starts immediately after turning on the smartphone or tablet and that provides the device with the instructions necessary for starting Android. In most cases, the bootloader is locked and does not allow installation of third party operating systems, so you need to unlock it in order to proceed. After unlocking the bootloader, the warranty of the device is invalidated and the data on the device is deleted.
- ROM – these are the modified versions of Android, created by third-party developers. In most cases, it is necessary to rely on a custom ROM to downgrade (i.e. restore an earlier version) of Android, as smartphone and tablet manufacturers are unlikely to provide obsolete versions of the operating systems dedicated to their own. device. There are also “custom” ones, that is modified.
- Recovery – is a small operating system independent of Android that allows you to install third-party ROMs or make full system backups. Not all smartphones and tablets on the market have a pre-installed recovery but, if there was, it would still have very limited functions. For this reason, it is necessary to install an alternative.
- Recovery mode – is the boot mode of the device that allows you to access recovery.
- Flash and flashing – are the terms that indicate the act of installing a ROM or a custom recovery.
- Fastboot – another boot “state” of Android, which allows you to edit delicate system files when the device is connected to a PC via USB cable.
- Brick – a device is said to be “bricked” or subject to brick when it cannot be started due to a software error. There are two types of brick: the soft brick , which finds resolution in a second flash procedure; and the hard brick which, on the other hand, can lead to the final breaking of the terminal.
- ADB – or Android Debug Bridge, is a component of the Android Development Kit (SDK) that is essential for sending commands from your computer to your device.
Secondly, it is good that you know right away that the Android downgrade , i.e. the act of installing an older version of the operating system, is frowned upon by smartphone and tablet manufacturers. Consequently, there is no official procedure that allows to obtain this result easily, on the contrary: this involves in any case the complete loss of the data present in the memory and can be extremely dangerous .
In fact, there is a real risk – even in the case of minor errors – of making the Android device permanently unusable ; moreover, “forcing” of this type invalidates the warranty of the device, therefore, to bring it back to life, you may have to spend a significant amount of money.
The reason is obvious: to bring Android to a previous version, it is necessary to overwrite the current operating system, “forcing” the installation of a different firmware, or a custom ROM (ie a modified operating system). To do this, it is necessary to act on very delicate parts of the device and, moreover, there is no standard procedure that can be followed: not only is it not possible to act on all the terminals, but the steps to follow differ, often significantly, between the phones / tablets from different manufacturers.
In light of what has been said so far, I advise you, even before opting for a drastic solution such as the Android downgrade, to attempt a reset of the terminal to the factory state , which involves the consequent recovery of the installed system apps as well. This last remedy, in most cases, proves to be decisive.
Regardless of the path you decide to take, I strongly urge you to create a backup of the data residing in the device memory, as both the factory data reset and the downgrade after installing custom ROMs involve the total loss of whatever is stored. in the device. If you have never backed up your data before, I refer you to reading my guide to Android backup .
How to restore Android to factory state
The procedure for restoring Android to its factory state does not involve particular risks, is officially recognized by all manufacturers, does not invalidate the warranty of the device and, very often, manages to solve most of the stability problems of the operating system, including those occurring as a result of an update.
I remind you, once again, that resetting Android involves the complete loss of the data stored on the device : for this reason, make sure you have made a backup copy of the same, before going on.
All clear? OK, let’s get started. To restore Android to the factory state, first go to the operating system Settings , by tapping on the gear- shaped icon located on the Home screen or in the drawer, then proceed by touching the System and Advanced items and then tap on the wording Reset options .
At this point, tap on the item Delete all data (factory data reset) , scroll to the bottom of the screen that is proposed to you, in order to enable the Reset phone button and, finally, unlock the device by entering the sequence or code set and answer affirmatively to the warning that appears below.
The recovery procedure, which could take several minutes, will thus be started and completed completely automatically. At the next login, you will be asked to carry out the first configuration phase of the device again ; in some cases, as a security measure, you should be able to enter the username and password of the previously configured Google account.
How to revert to the previous version of Android
If the recovery of the operating system did not have the desired effect and, as a last resort, you have decided to go back to the previous version of Android , then follow the instructions that I am about to give you in the following sections of this chapter.
Before continuing, however, I would like to repeat once again the risks you face, to allow you to act in full awareness of what you are about to do: unlocking the bootloader causes the complete cancellation of the device memory and invalidates the guarantee; the recovery / ROM flash can cause the brick of the device , making it unusable, and it is essential to download a ROM compatible with your device , otherwise you risk, even in this case, the brick. Personally, I will not be held responsible in any way for any damage you may cause to your device.
Unlocking the bootloader
The first step to take to flash a ROM containing an older version of Android is to unlock the bootloader of the device in question. To do this, you will first need ADB and its drivers: to get them on Windows, visit this web page , click on the Download button and wait for the software installation package to complete. Once the file is obtained, start it, then press the Next button three times in a row, then click Yes and Close .
The next step allows you to install Fastboot , another software used to manage some delicate parts of the device: therefore connect to this website , click on the Download version XXX Portable link and then press the Click Here to Start Download and Primary Download buttons , to copy the package to your computer. Once the download is complete, extract the file to a folder of your choice, convenient to remember: you will need it later.
Once the installation of ADB and Fastboot has been completed, you must activate USB debugging on the device on which you intend to intervene: therefore access the Android Settings , go to the System and Information on the phone / device sections , locate the word Build number and tap on it seven consecutive times, until you see a message about activating developer mode .
Now, go back to the previous menu, tap on the Developer Options / Development Options item, locate the USB Debugging item and move the relative lever from OFF to ON , responding affirmatively to the warning proposed later.
After this step too, you can finally proceed with the actual unlocking of the bootloader: however, there are no standard steps to perform this operation, as it differs from device to device. For example, manufacturers such as Sony , Motorola and Xiaomi officially provide instructions and tools for unlocking the starter (nevertheless, the procedure still invalidates the warranty of the device), while for others you will necessarily have to search for information on Google , typing phrases such as unlock bootloader. [smartphone / tablet brand and model] .
To give you a practical example of how to act, I’ll explain what the Motorola Moto G bootloader unlocking procedure consists of.
- Turn off your phone completely, boot it into Fastboot mode by pressing and holding the Power and Volume keys at the same time – and, when it turns on, connect it to your computer via USB cable .
- Open the folder on the computer where you extracted the Fastboot files, right-click in an empty part of it by pressing and holding the Shift key on the keyboard and select the item Open PowerShell window here from the proposed context menu.
- Type the command
fastboot oem get_unlock_datain the PowerShell screen, press the Enter key on the keyboard and note the identification code of the phone which should appear shortly after.
- Go to the Motorola website , log in with your account, paste the identifier you wrote down just now in the appropriate text box and wait for the bootloader unlock code to be returned.
- Go back to the PowerShell screen and, still keeping the phone connected and in Fastboot mode, type the command
fastboot oem unlock [codice di sblocco]and wait for the device to be unlocked.
- Don’t close PowerShell or unplug your phone – you’ll still need this window before long.
If, on the other hand, you have a Google- branded device produced starting from 2014 ( Pixel or Nexus ), you have to act in a slightly different way to what we have seen above: after starting the smartphone in fastboot mode and opening the PowerShell window, type the command
fastboot flashing unlock, if yours is a device manufactured starting from 2015, or
fastboot oem unlock, for those manufactured on an earlier date. In this case, there is no need to obtain an unlock code.
Installation of recovery
Once the bootloader has been unlocked, you can finally proceed with flashing the recovery , an essential step to be able to install a custom ROM on the device. Among the most common recoveries is the TWRP : to get the most suitable file for the smartphone (or tablet) in your possession, go to the page I linked to you just now and, after selecting the brand and model of your device, download the image file of the recovery that is right for you.
Please pay close attention to this step: downloading an incorrect version of the recovery could brick your device.
In any case, once you have obtained the recovery image, flash it via Fastboot : also in this case, the steps to be taken may change from device to device. Generally, what you have to do is resume the PowerShell screen left open previously and, after making sure that the phone is still connected to the computer and in Fastboot mode, type the command
fastboot flash recovery recovery.img, replacing recovery.img with the full path of the image previously downloaded.
Once the recovery flash is complete, you can disconnect the device from the computer, shut it down and close the PowerShell window.
Once the preparation of the device is finished, it is time to download a ROM based on the old version of Android that you are interested in obtaining. On the Net you can find many custom ROMs of this type, in the form of a zip package : before downloading any ROM, make sure that it is tailor-made for the phone or tablet model in your possession and, above all, that it is based on the version. of Android you are interested in obtaining. If you download a ROM that is not suitable for your device, you risk bricking it and irreparably compromising its operation.
Note that some ROMs do not integrate Google apps ( Play Store , Play Services , Gmail, and so on) by default: in this case, you need to get the gapps.zip file that best suits your ROM and device.
In any case, once you have identified the ROM of your interest, you have to copy it to the memory of the Android device and then flash it through the previously installed recovery. Also in this case, the steps may vary according to the type of recovery chosen: below I will show you how to proceed with TWRP.
- Turn on the smartphone or tablet in recovery mode : generally, you can achieve this by pressing and holding the Power and Volume Up or Power, Volume Up and Volume Down keys . For more information, Google for phrases like recovery mode [device make and model] .
- Connect the device to the computer again via USB cable and tap the Mount button located on the recovery home screen, so you can access the device’s internal memory as a USB key.
- Copy on the Android device the .zip file containing the ROM of your choice and the package containing the gapps (if necessary).
- Go back to the initial recovery menu, tap the Unmount button and then the Install button .
- Select, with a tap, the previously copied ROM . If you need to install the gapps as well , press the Add More Zip button and select the package containing the Google apps.
- At this point, swipe the slider to the right Scroll to install and wait patiently for the procedure to be completed.
- Once the flashing is complete, tap the Clean Cache / Dalvik button , swipe the appropriate bar again to the right and, when the cleaning is complete, press the Reboot button to restart the device.
If everything went right, at the next start, the smartphone or tablet should show you the first configuration screen of the chosen ROM, a sign that the flashing procedure was successful. The first boot of the device may take longer than usual – don’t worry, this is normal.