Come tomorrow, it is expected that Apple’s iWatch will shift from rumor to reality, at long last truly launching the wearables category, according to new Forrester research. “Apple’s iWatch category launch will be one of its most important and brand-reinforcing launches in years,” writes Vice President and Principal Analyst James McQuivey. “Apple will show again how computing platforms are won or lost on the one-two punch of eager consumers and hungry ecosystem partners.”

How eager are consumers? According to new Forrester data, 25% of US online adults anticipate purchasing a wearable device in the next year, and 42% are specifically interested in wearing it on their wrist — assuming it’s a service of interest, offered by a trusted brand.

And that’s exactly what Forrester expects Apple to offer. So much so that Apple will sell more wrist-based wearables through 2015 than anyone else has cumulatively sold, including fitness companies that have been selling trackers for years. How is this success possible? Up until now, vendors like Nike, LG, and Samsung have sold products. But Apple will do what it does best: It will build and sell the wrist-based wearables category.

However, despite the fact that Apple will don the wearables innovator crown through 2015, it will not sustain dominant market power as it has with the tablet market. Google and Amazon are both positioned to ride Apple’s coattails, thanks to their existing digital customer relationships — helping to reduce Apple’s share of units sold to less than 50% during 2016. As for the other players: “Everyone else will struggle to become anything more than the next Flipcam, Palm Pilot, or Nook eReader.”

While Tuesday is expected to be a big boost to the wearables market, Forrester also warns not to get too caught up in the latest wearables hype. The most successful firms will think beyond wearables and focus on understanding consumers’ expectation to be served in the micro moment — the instant quick information is needed and can be obtained with just a glance at the device or wearable on hand. Firms that master serving customers in these micro moments will advance on the latest engagement battleground.

Learn more about Forrester’s Apple predictions here.