Earlier this month, Google's upcoming Android OS version was publicly confirmed at the yearly Google I / O event, and unsurprisingly the search engine giant revealed a number of brand new features which will apparently be part of Android N once it reaches its final release. One of the many features introduced in the first previews of Android N is the ability to change how large items appears on a smartphone's display. This option has been offered by custom ROMs, but now it appears that Google might want to support manual DPI scaling natively. Interestingly enough, Samsung and its latest version of TouchWiz UI based on Android 6.0 Marshmallow seems to be one step ahead of its time, as an XDA-Developer user has discovered a way to enable DPI scaling on the new Samsung Galaxy S7. The option is hidden in TouchWiz UI, but apparently it can be enabled using a third party launcher.
As smartphone displays continue to increase in resolution, manual DPI scaling might become a standard feature in future devices. In layman's terms, DPI scaling can be used to increase or decrease the size of elements in the user interface (such as icons, text, lists and so on), while maintaining the same display resolution and pixel density (PPI, or pixels per inch). In the case of the Samsung Galaxy S7, manual DPI scaling appears to be a hidden feature within the latest version of TouchWiz UI. Although accessing this feature through TouchWiz doesn't seem to be doable at this point in time, an XDA-Developer user has discovered that DPI scaling can be enabled on the Samsung Galaxy S7 (and presumably other Samsung flagships running the same version of Android 6.0 Marshmallow + TouchWiz UI), using a third party launcher called Nova Launcher.
To enable the feature, Samsung Galaxy S7 users need to download and install Nova Launcher from the Google Play Store and temporarily set it as the default launcher. Then, tap and hold an empty area on the home screen to bring up the "Widget Selection" pop-up, and drag & drop the "Activities" widget on top of the home screen. From the "Activities" list, scroll down to and expand the "Settings" option, and then tap ".DisplayScalingActivity" and return to the home screen. Lastly, tap the "Settings" widget newly added to the home screen, and choose between "Standard" and "Condensed" DPI options. Wait for the device to reboot and apply the changes, and once done you can switch back from Nova Launcher to Samsung's proprietary TouchWiz UI while maintaining the selected DPI setting. Granted, the list of DPI options is limited and offers only the "Condensed" option aside from "Standard" / stock, but it is better than nothing. Hopefully, Samsung will make DPI scaling officially available on the Samsung Galaxy S7 and other Android 6.0 Marshmallow-based devices through a future software update. Until then, the Nova Launcher method for DPI scaling appears to be the only one that doesn't require rooting your device.