Konnected boards just relay the state of your sensors to the supported home Automation platform of your choice. I personally use Samsung Smartthings, and have heard of people using home assistant. Unsure what other platforms are supported.
Smartthings is a combination of hardware and software. A hub, which uses radio signals such as zwave zigbee and wifi to communicate with other smart home hardware such as light bulbs, door locks, etc. The hub is connected to your home wifi/network/internet, and communicates to your Smartthings account and Mobile App. In the Smartthings app is where you will see and manage your various smart home devices, include the sensors that are wired to the konnected boards. In the app is also where you will setup your Automatons and create custom rules for how these devices interact with each other. Ex. If alarm is active, and front door senser detects door has opened, turn on siren, and turn entry way smart full color light bulb to red.
As for action tiles, this is just another program/platform for interacting with smartthings, most devices interacted with in actiontiles come from smartthings, actiontiles is popular cause it has a much nicer look then interacting directly with the smartthings app.
May seem like a lot to figure out but really isn’t to bad once you get rolling, first step is probably gonna be purchasing a smartthings hub, I suggest getting it in a starter kit that comes with a few sensors etc. Usually a better value.
Best of luck
S.M.A.R.T. FLX NY