The much awaited launch of Apple Watch is believed to be a success despite the absence of official data pertaining to its sales. According to research firm Strategy Analytics, Apple Watch has secured 75% market share in the global smart watch segment as the estimated shipment was at four million units during the second quarter of 2015.

Strategy Analytics' latest report reveals that global smart watch shipments registered a robust 457% growth year-on-year (YoY). However, Apple has not revealed the actual sales number so far.

The absence of official sales data from Apple has led to many estimates as several research firms are coming up with their own projections contradicting each other.

According to some analysts' estimates, Apple Watch sales could be in the range of three million to five million during April and June 2015. Apple didn't mention about sales number of Apple watch in its latest earnings report for the third quarter.

However, company's chief executive Tim Cook claimed Apple Watch had a "great start."

Considering the latest earnings report for the third quarter, some analysts reduced the sales forecast to 1.5 million to three million watches.

Just by going by the first quarter sales performance, one can't rule out the Apple Watch success and its impact on the smart watch segment. 

According to Yahoo News, five key features will help Apple Watch crush its market competition. These are design, software, Apps, Apple Pay and Force Touch. These features would make an enticing platform for wearable devices.

Apple is set to repeat its success of iPhone and iPad in smart watch segment too. The quality of third-party iOS apps are proven to be excellent in iPhone and iPod and it's expected to repeat the same magic in smart watch market as well.

Another advanced feature will be Apple Pay. Of course, it might take some time as it has to be available on all devices and retail establishments. The users of Apple Watch can access in-store Apple Pay payments.