macOS comes with a built-in app switcher that can be activated by using the Command + Tab hotkey, but the user does not have any control over the utilities that are to be included in the bar or the hotkey.
HyperSwitch is yet another keyboard window switcher for your Mac. It will perform mostly the same function but it will also allow the user to decide on various details, such as the windows that re to be included, the delay period, the appearance, and so on.
You can choose to see app icons, and the window previews only show when you highlight one of the apps or you can tell it to show you individual windows all the time.
Download: HyperSwitch 0.2.588-dev