Traditional pill reminders are pill containers with electric timers attached, which can be preset for certain times of the day to set off an alarm.
More sophisticated pill reminders can also detect when they have been opened, and therefore when the user is away during the time they were supposed to take their medication, they will be reminded of it when they return.
This reminder can be in the form of a light, which also helps for deaf or hearing-impaired users.
[1] Some of these applications might effectively support adherence to taking medications.
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