This FAQ is now completely out of date, but it’s so old that I can no longer edit the first post. However, a lot of things have changed and there’s a much simpler method now. See the new 2017 FAQ at the following link:
Echo and Google home only recognize some device classes, specifically lights, switches, thermostats , and maybe locks.
The official SmartThings/Alexa integration can run routines, but only routines that are limited to the device classes above.
IFTTT has the same issue. The SmartThings service/channel can turn a single device on or off, but it doesn’t show routines or modes or smart home monitor status.
So how can you use your voice assistant or IFTTT to change your mode, unlock a lock, or change smart home monitor armed status if the voice assistant/IFTTT won’t work with those kinds of devices?
Fortunately, it’s easy.