Well, it's 'only' taken Apple a year to finally approve Valve's Steam Link mobile app, which has been approved, then pulled from the App Store. At the time, Apple legal services cited 'business conflicts' as the reason for the snub.
Note that the Android version was freely available throughout this entire period, but Apple obviously weren't in a hurry to approve the iOS one, and we didn't get any explanation on what exactly happened to change their mind.
Steam Link was initially cleared for launch on 07 May 2018, but Apple reconsidered their stance three days later, opting to pull the game from the App Store.
Apparently, some things that constituted "business conflicts with app guidelines" had been overlooked by the original team that did the reviewing.
Valve tried to fight back saying that their app is just another "LAN-based remote desktop similar to numerous remote desktop applications already available on the App Store", but it did little to appease Apple.
"The Steam Link app brings desktop gaming to your iPhone or iPad. Just pair an MFI or Steam controller to your device, connect to a computer running Steam on the same local network, and start playing your existing Steam games", says the description on the newly added App Store .
Looking at the description though, Steam Link isn't much different from Remote Desktop or Team Viewer, which was one of the points that were raised earlier, both by Valve and the general public.
Unfortunately, it didn't seem to help, as Apple decided to stick to their decision until now, so Steam Link's iOS conquest is likely to lag behind the Android version.
On the other hand, we're talking about a pretty useful app that seems to be running great, judging by the reviews at least, and we've no doubt it will manage to cut out its piece of the Apple pie.