The smartphone companion app for the Nintendo Switch is now available in many regions, downloadable via both the App Store and Google Play.
Free until the end of the year, the Nintendo Switch Online app will reportedly only support Splatoon 2 for now – but will allow access to party chat lobbies and invites, as well as SplatNet 2 (for in-game shopping and gear/stat checking purposes). As for the voice chat aspect, it’ll only work once you’re already in game, and you won’t be able to access any of your phone’s other features (like texting or other apps) while chat is active.
The app is rolling out now in many regions, and should be available via your app store’s search function if currently available to you. Just be sure to search “Nintendo Switch Online” if you want the right one. 😉