Vapor-emitting devices according to various embodiments of the invention
include active end of use indicators to warn users that it is nearing the
time and/or time to replace the vapor-emitting device or a refill for the
device. Some embodiments of the vapor-emitting devices include intrusive
actuation of the end of use indicator, while other embodiments include
non-intrusive actuation of the end of use indicator. The indicators may
be visual and/or auditory cues for notifying users it is nearing the time
and/or time to replace the vapor-emitting device or a refill for the
device.