Prior to Monday's Apple event that is likely about the Apple Watch, there are certain companies working at a secret lab within Apple's headquarters to fine tune their Apple Watch apps that will launch on the watch and/or be demonstrated during Monday's keynote.

Bloomberg is reporting that Facebook, BMW, United Continental Holdings and others have been working at Apple's secret lab for weeks.

So what makes it a "secret lab?" According to one of Bloomberg's sources "Internet access is blocked inside the rooms and no outside materials can be brought in to the labs with the test watches. The companies, sometimes sharing a room, must bring in source code for their apps on a computer hard drive that can't leave Apple's headquarters. To prevent information from leaking out, Apple is storing the code and sending it to the companies closer to the watch's introduction date."

Stephen Gates, a vice president and creative director for Starwood Hotels & Resorts Worldwide Inc., which is building a watch application to unlock hotel-room doors, stated that "There's a lot of confidentiality." Gates said that he's made several trips to Cupertino to develop the software.

A big challenge for Apple and its developers is building applications that are useful without being annoying. Apple has recommended that developers be judicious about interrupting people with constant alerts that will buzz their wrist or drain the battery.

Yesterday we reported that Strategy Analytics is forecasting Apple will sell 15 million Apple Watches this year, with J.P. Morgan forecasting 26 million. It was noted in Bloomberg's report that Katy Huberty, an analyst at Morgan Stanley, is estimating that Apple may ship as many as 30 million watches in the first 12 months. While that number is in a different time frame than the others, it's still a very confident number that guarantees that Apple will be the wearables/smartwatch leader, miles ahead of the competition.

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