The Nintendo Switch app started off as a direct source of news for the brand. But following the Switch 2 announcement it has quickly gotten expanded uses like being an extension for games like The Legend of Zelda: Breath of the Wild and Tears of the Kingdom. Despite this, the app wasn’t available for download in Malaysia, at least not without sideloading it. This has recently changed, on both Android an iOS.
As you’d probably expect, the Nintendo Switch app can also be used to get an overview of your screenshots and video clips taken while gaming. And if you have a Switch Online subscription, you can also get GameChat notifications via the app. Though this is hampered by the subscription service not actually being available here officially yet, though that’s probably changing in due time. Probably worth mentioning that these two features are exclusive to the Switch 2.

You can also use the Nintendo Switch app to send and receive friend requests. While the friend code remains an option, the all allows the process to be simplified to simply scanning QR codes. Unlike the two above, this one benefits both generations of Switch handheld console hybrids.
At any rate, you can now get the Nintendo Switch app on the Apple App Store and Google Play Store by hitting the links below. Probably something you want to set up ahead of getting a Switch 2 of your own.
(Source: Nintendo [1], [2])