If your Galaxy A8 (2018) is currently sitting in a drawer because it is too slow, install a custom ROM. It transforms the device into a usable backup phone.
Open Gmail, Chrome, or Spotify on stock: you wait 2–3 seconds for the app to draw the UI. Open the same apps on a (Pixel Experience or DerpFest): they launch in 0.8 seconds. The difference is the animation scales and the absence of "Samsung Internet" intercepting links. galaxy a8 2018 custom rom better
Flashing custom ROMs requires an unlocked bootloader, a PC, and some technical skill. It voids your warranty (expired anyway) and carries a risk of bricking the device if steps are followed incorrectly. Always backup your EFS partition first. If your Galaxy A8 (2018) is currently sitting