Your app can access the local Wi-Fi network to connect with devices, and reach the internet to talk with external APIs.
Homey can access devices on the LAN, for example on
192.168.1.100. No extra permissions are required to access these devices locally.
The preferred way of connecting to LAN devices is by discovering them automatically. Learn more about connecting to LAN devices in the Discovery guide.
Homey can talk to the internet without extra permissions. Many Web APIs can be accessed this way.
Many modern Web APIs authenticate using OAuth2, you can lean more about creating Homey apps that connect to OAuth2 Web APIs by reading the OAuth2 guide.
Homey can receive external webhooks, even if it's behind a user's router. You can learn more about receiving webhook events in Homey apps by reading the webhooks guide.