NSDSWebApp

NSDSWebApp is a system app that usually comes installed on all Samsung devices, but as its own package name suggests, it's actually developed by Ericsson. The purpose of this app is to help your device establish and maintain phone calls via Wi-Fi. For this reason, it's important not to uninstall or block the app, although even if you did, all your Android device's services would continue to work without a problem.

The app is tiny and takes up just over 1 MB, so it doesn't need much space on your device's memory. Similarly, NSDSWebApp only consumes resources during calls via Wi-Fi when using other apps such as Skype, Whatsapp, Telegram, or Wechat; and because it's supposed to improve call fluidity, it more than makes up for the increase in battery usage.

You should only uninstall NSDSWebApp if you notice that it's draining your Android's battery over a prolonged period of time, even when you're not making VOIP calls. In cases like this, it may be a good idea to uninstall and reinstall it. If the problem persists, there's most likely some incompatibility between apps.

NSDSWebApp is a system app that, in principle, you should try not to mess with. The app automatically runs in the background whenever you make calls via Wi-Fi, so you don't have to worry about it.