Switch Online for Mobile Released
Nintendo has released the Nintendo Switch Online app for Android and IOS, giving users the ability to voice chat for their online services such as Splatoon 2.
A Nintendo Switch must be registered to your Nintendo account for you to be able to sign into the app, as it uses your Nintendo ID to authenticate with.
Edit: It appears they have marked the service for "Server Maintenance", giving out error code: 2817-0700. It seems we will have to wait a little longer to actually use the app itself.
You can grab them here:
Android: https://play.google.com/store/apps/details?id=com.nintendo.znca
IOS: https://itunes.apple.com/us/app/nintendo-switch-online/id1234806557?mt=8