Native Widescreen: Many GameCube games have native widescreen (anamorphic) support. Stretch: You can stretch the 4:3 image to 16:9, which, while filling the entire screen, doesn't look so nice. There's several way to do so, but for all of them to work, you have to set your game aspect-ratio ratio to "Stretch to window" (in game.
As for knowing what's your game ID, you can get it from the GameTDB website, Dolphin Emulator on your PC (right click on your game and go to the "Info" tab) or by holding the A button on your game in Dolphin Emulator for Android and selecting any of the submenus (the game ID will be shown in the top title bar). To do so, you will need a text editor such as (for exemple) Notepad++ on PC. ini file that you have to name according to your game ID in "dolphin-emu/GameSettings". To use it, simply copy the content of the provided template above and paste it into an. Also, it allows you to use AR code for proper widescreen "hacks" and let you set per games aspect ratio and so on. Many games require specific settings to run properly on the SHIELD (and actually many other devices). Per game settings allow you to tinker precisely each of your games to squeeze out the best of them on your device.