Ghana, Nepal, Nigeria and Singapore occupied the next four places, while American internet users were 13rd, data showed.

According to data from Google Trends, the number of Google searches for iPhone 11 by Vietnamese netizens exceeded 100,000 on Monday. At midnight of Tuesday, the search volume for iPhone 11 in Vietnam soared, with an increase of 500 percent compared to the last 24 hours.

It has also become the second most-searched keyword in Vietnam. Previously, this keyword only reached a few thousand searches per day.

The most popular searched keywords were "the price of iPhone 11", "iPhone 11 Pro", "iPhone 11 launch event," in Vietnamese.

An unnamed SEO (Search Engine Optimization) expert said it could be likely that many Vietnamese people were confused about the launch time of the iPhone 11 due to the time zone difference.

The launch of Apple iPhone 11 series will be held at the Steve Jobs Theatre, a dedicated venue, at its Silicon Valley headquarters in Cupertino at 12 p.m. Tuesday (local time), which will be at midnight of Wednesday (Hanoi time). The iPhone 11, iPhone 11 Pro, and iPhone 11 Pro Max are expected to make their debut then.

The phone is likely to be available as a high-end "Pro" large version, a standard sized version and a cheaper LCD version of the iPhone 11, the U.K.-based Telegraph reported.

Apple has made some big changes as to how consumers can watch its live event, including broadcasting it on YouTube for the first time.

A report issued in January 2018 by We Are Social, a social media marketing and advertising agency, said around 75 million, or almost 80 percent of the population in Vietnam use smartphones.