When the Nintendo Switch Online App launched earlier in the year along with Splatoon 2 , it caused some disturbance in the community. It is oddly isolated from the Switch console and had bizarre issues like the game chat refusing to function unless the player’s device stayed on the Nintendo Switch Online App screen. That may have been an unintentional problem, as an update has arrived to set things right.
Both the iOS and Android version of the Nintendo Switch Online App have been updated to version 1.1.0. The patch notes state that the app will allow voice chat to function while other apps are open and while the device is in sleep mode. However, the app also notes that Android devices on Android 6.0 or later will need to have power-saving mode off for this to work.
It sounds like, to run voice chat using the Nintendo Switch Online App, a lot of power is drawn. This update probably means that Nintendo had to find efficiencies elsewhere in the app to make the power drain less intense during this specific use.
Source: GameSpot