Appid Steam 〈Mobile〉

If you're a Steam developer:

With Steam Deck and SteamOS, AppIDs now control: appid steam

When you install a game, Steam looks at the AppID to determine which Depots your operating system needs to download. This system allows developers to ship massive HD texture packs as optional Depots under the main AppID without forcing every user to download them. If you're a Steam developer: With Steam Deck

AppID is a unique identifier assigned to each game or application on Steam. Here are some helpful features and uses related to AppID: appid steam