The days of having to enter your cable account login details into every individual TV app on iPhone, iPad, and Apple TV are coming to an end — maybe. Depending on who you get your cable from. As MacRumors notes, today Apple rolled out its single sign-on feature for iOS, which lets users enter account details (for participating cable providers) just once and then be automatically signed into TV Everywhere apps. Here’s Apple’s help page that explains the feature and how to enable it.

Right now, that list of providers is limited to the following cable and satellite companies:

• CenturyLink Prism
• DirecTV
• Dish
• GTA
• GVTC
• Hawaiian Telcom
• Hotwire
• MetroCast
• Sling TV

Apple’s missing some big names here: Comcast, Time Warner Cable, Charter, Verizon FiOS, and Optimum are all absent from the launch list. Apple expects to add more cable providers over the coming weeks and months. It’s at least got satellite pretty well covered with DirecTV, Dish, and Sling TV. (The new DirecTV Now service does not yet appear to be supported.)

To make matters a little more confusing, single sign-on only works for certain apps — and even then, sometimes only the iOS or Apple TV version. Here’s which ones support the feature on day one:

Again, there are a lot of important apps that people like missing, such as ABC, CBS, Disney, WatchESPN, HBO Go, and many others. This one’s up to the networks and their app developers to fix if they want to. No one’s being required to add single sign-on to their software; it’s strictly a convenience thing. And with those omissions, Apple acknowledges that right now you’ll still be entering login info repeatedly. Even all these months after the feature was first announced. Sigh. It’s a start, I suppose.