Apple rolled out a number of iOS App Store rule changes on Wednesday, and the one that catches your eye will likely depend on your mobile-app interests. The biggest change, at least in terms of number of people likely reached, is a tweak to a major rule about video games on the platform: how loot boxes are advertised to players.

9to5Mac was among the first sites to dig into the rules update and pick out the big changes, and it found that Apple has opted to use the term "loot boxes," which it defines as "mechanisms that provide randomized virtual items for purchase." Now, any game or app that utilizes such a random-item system "must disclose the odds of receiving each type of item to customers prior to purchase."

While loot-box mechanics have landed in news headlines thanks to major console games, the practice was popularized long ago in free-to-play mobile games on iOS and Android, typically in a Japanese genre known as "gacha." The most prominent example of this type of mobile game in the West is arguably Nintendo's Fire Emblem Heroes, which launched on all smartphone platforms earlier this year and encourages players to accumulate fighters, knights, and mages by getting them out of virtual slot machines—which dole out random rewards, not static or guaranteed ones. Currency for those slot machines can be earned by playing the game, but you can get that currency faster by paying real-world money.













Fire Emblem Heroes offers an example of how this odds-listing system could work in action. Now, when you mull over which of the game's slot machines you want to pay currency to (there's typically a couple to pick from), you should expect to see a list of every single hero in the game, along with a variety of "rarities" that determine strength and other combat attributes, with a percentage likelihood attached. This will probably look like a blind-box listing from a toy seller like Kidrobot, showing that some hero unlocks are much rarer than others.

China began enforcing similar rules for online game operators in May of this year. At that time, when popular game makers like Blizzard complied, they showed how vaguely written rules about loot-box odds can be taken advantage of to leave players in the dark. In Blizzard's case, the company simply announced that each of its loot boxes is guaranteed to contain one "rare"-class item, while players have a 1-in-5.5 chance to earn "epic"-class items or a 1-in-13.5 chance to earn "legendary"-class items.

However, this disclosure didn't confirm whether item types, ranging from valuable costumes to worthless "graffiti tags," had their own percentage chances. Apple's vaguely written rule would allow game companies to post similarly unclear descriptions.

Still, Apple has beaten Google to the punch in announcing this kind of loot-box odds rule, as Android's Google Play contains no such rules or requirements.

Apple's Wednesday update to the App Store rules includes a few other changes. Cryptocurrency apps must now be associated with major banking firms if they offer "Initial Coin Offerings ("ICOs"), cryptocurrency futures trading, and other crypto-securities or quasi-securities trading." VPN-service apps must now clearly state what user data is gathered and how it's used, and language has been added to reflect local laws about VPNs. And a rule about "template"-designed apps tries to strike the balance between kicking out crappy clone apps and still allowing small devs to rely on template services to deliver their legitimate apps. In short: the language appears to still allow these apps but will likely put them in a default higher-scrutiny queue before being approved.