Historically, the users of Android, unlike iOS, is quite tolerant backups. Whether due to lack of clear backup mechanism, whether because of the General illiteracy of the audience, but to meet someone with an Android smartphone, which would be regularly kept copies just in case, to find it sorely difficult. Apparently, Google has decided to propose to the developers to keep user data on their device even after deletion. However, only those that are running Android 10.
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After Android 10 some users have noticed that in the process of removing a number of apps they offer to save your data on the device. Most often it is the instant messengers and social media apps that ask permission to leave a cache in memory so in case of re-installation to provide the user with the same set of data that it had before deletion. However, the mechanism for saving data can be embedded into any application. You will thus not lose past progress, which sometimes can be extremely helpful.
However, to call this backup can only be a stretch. Despite the fact that stored data can be stored in the memory indefinitely, even if the application that saved them, has long been removed, roll back the device to factory settings will lead to their complete removal. For this reason, to access your saved progress after you clean the drive will be available, unlike the data from the backup, which for security purposes is discharged to the cloud.
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However, for all the shortcomings of the idea to store data in the device memory can come in handy, for example, for applications whose job involves constant communication with the Internet. This may be true for games, media players or different kind of tools with the saved settings. As a result, even if you delete third-party camera app from your device, after re-installing the set parameters will be restored automatically pulling up a saved cache files.
Why accumulate cache files
However, this mechanism has a downside. The fact is that if all the developers will build tools to save data in their apps, over time they can accumulate so much that they will take up most of the built-in storage. And since Android so wasteful relates to memory cache without parsing any data, users will have to look for ways of cleaning a drive than often used by cyber criminals and issue virus program for utilities-cleaners and thus infect the devices of their victims.