For those who do not only want to search for their AirTags via iPhone, but also find it an advantage if the small key fob for the AirTag is also visible at night, self-luminous variants are something for them.
These glow in the dark tags show you the way to your keychain even at night. Handy if you still have your iPhone with you, but the battery is empty and the keychain has fallen out of your pocket somewhere on the way home.
The self-luminous tags for your AirTags are not expensive either: for around one dollar they are available on Aliexpress.