What is a SmartApp
SmartApps are applications that allow users to tap into the capabilities of connected devices to automate or perform specialized functions. Many different types of SmartApps are either pre-installed or created by third-party developers:
Event Handler SmartApp
Event Handlers are the most commonly developed in Smart Home Hub. These allow you to subscribe to Events from other devices to trigger its own pre-defined automation.
Solution Module SmartApp
These apps exist within the dashboard of Smart Home Hub and are containers for other SmartApps. These allow the combination of SmartApps to work together.
Service Manager SmartApp
Service Manager SmartApps are used to connect to LAN or cloud devices such as Sonos or WeMo devices for example.
Pre-installed Smart apps are already installed in your SmartThings Connect, you can use these as soon as you have paired devices to your Smart Home Hub.
Smart Home Monitor
HomeCare Wizard proactively makes sure all connected devices are in their best condition. This Smartapp is used for smart refrigerators, air conditioners, and washers.
Smart Lock Guest Access
Creates and manages guest access codes for your Smart Locks.
Severe Weather Alert
Get a push notification when severe weather is in your area.
Enhanced Auto Lock Door
Automatically lock a specific door after X minutes when closed and unlocks it when open after X seconds.
Ready for Rain
Warns you if doors or windows are open when inclement weather is approaching.
Control your lights and switches based on a variety of inputs including motion, open/close, presence, mode changes, specific times, sunrise/sunset, and more.
Ties multiple colored lights to one specific light setting.
Keep me Cozy
Enables you to pick an alternative temperature sensor in a separate space from the thermostat. Focuses on making you comfortable where you are spending your time rather than where the thermostat is located.
Thermostat Mode Director
Changes the mode of your thermostat based on the temperature range of a specified temperature sensor and shuts off the thermostat if any windows/doors are open.
Compares two temperatures - indoor vs outdoor. Sends you an alert if windows are open or closed. If no outside thermostat is used, then it will use the location's temperature.
Control your speaker, play a sound, a custom message, when an event occurs or if the system mode changes.
Alerts you if a door is knocked, but not opened.
Custom SmartApps are developed by any third-party developers. There are limitless custom smartapps to do exactly what you want SmartThings to do. Any missing functions that you wish were present in the hub can be added using SmartThings API.
Custom SmartApps can be built using SmartThings developer page (previously through SmartThings IDE) and must be manually installed before you can use it.
Recommended custom SmartApp(s).
There are many SmartApps available, but there are only some that are used by home automation enthusiasts. These are a few of the most widely praised SmartApps available.
WebCoRE is a very advanced rule machine that allows you to create extremely complex automation (if, if-else, then), if you can't do what you want with any SmartApps or Custom Automations, use WebCoRE. As a rule machine, it can pretty much do anything.
There are unexposed functions from Z-Wave in Smart Home Hub such as configuring Parameter settings or setting Group Associations. This tool doubles down as a debug tool if you find any issues in any of your custom device handlers or Smartapps.
This tool is mostly used to assign Group Association (Z-Wave device to Z-Wave device direct communication), and Parameter settings (internal custom settings).
Developing your own SmartApps
You'll need to sign up to be a developer through this link to get started: SmartThings developer page
Becoming a developer will allow you to integrate new devices or create new SmartApp(s).