Initial details on Apple’s strict rules for Apple Watch app development were revealed last week, but as the April 24th release date nears we’re starting to hear more about the bizarre secrecy surrounding the wearable. In an email to potential Apple Watch developers earlier this week, obtained by The Verge, Apple has started to invite app developers to WatchKit Labs across the world. There’s a strict attendance policy to enter WatchKit labs, involving government-issued photo ID and the need to bring a near-final version of an Apple Watch app on a MacBook running Yosemite.

"Tape will be placed over the cameras on your MacBook and iPhone."

This all seems reasonable, but Apple specifically states "you may bring one personal iPhone into the lab," noting that no other equipment is allowed (apart from the MacBook). "You agree that tape will be placed over the cameras on your MacBook and iPhone (or on your team member’s MacBook or iPhone) since no photography or video will be allowed at WatchKit labs." Tape is certainly one way to prevent leaks, but it’s not clear what Apple is trying to hide here given that public previews of the device will be held in a month and members of the media have had a closer look at working watches earlier this week.

A Bloomberg report revealed that Apple is also blocking internet access, and developers cannot bring outside materials into the room that houses the Apple Watch. Developers are sometimes forced to share a room to work on the watch and have to leave the code for apps in development on hard drives that can't leave Apple's offices. Apple is now planning to hold its secretive labs in Sunnyvale, London, Sydney, Tokyo, Beijing, and Hong Kong. If developers agree to the strict rules then they also agree "not to take any photographs, video recordings, or screenshots of Apple Watch, including but not limited to any application trailers of your application running on Apple Watch, or any pictures inside of the WatchKit lab venues."