fstrim is used on a mounted file system to remove (cut) blocks that are not used by the file system. This is useful for solid state drives and thin allocation storage.
But why is it used in this Android app?
Almost all Android devices use NAND chips for data storage. Due to the operation of NAND chips, they can slow down considerably after a while. The adjustment would help restore the performance of NAND chips to their original value.
Supported Android
{4.0 and UP}
Supported Android Version:-
Jelly Bean(4.1–4.3.1)- KitKat (4.4–4.4.4)- Lollipop (5.0–5.0.2) – Marshmallow (6.0 – 6.0.1) – Nougat (7.0 – 7.1.1) – Oreo (8.0-8.1) – Pie (9.0)