A file system is a mechanism by which files are placed and organized on a storage device or on a memory; Several operating systems, though they can run on the same device, probably have two different file systems. For example, Windows uses the NFTS file system, Mac OS the HFS + and Android EXT4 system.
According to some sources Google would be thinking of supporting on Android Btrfs, one of the file systems used on the Linux system; Btrfs has a GPL license but at present still has some instability. A company engineer confirmed that Google would be “considering Btrfs for a potential use on Android.”
However, Btrfs does not natively support the ability to encrypt files, while Google has always been entrusted to EXT4 over the years, which naturally has this option through what is now known as fscrypt in the Linux kernel and is also shared by F2FS.
Google’s interest in Btrfs may motivate some developers to work on this solution; Last year there were patches for Btrfs encrypted files but they have never been completed. We’ll see what’s going to happen.