The document said the enquiry would focus on "new and emerging markets that are shaping our economy and society".
Regulators wanted to know if Apple has rejected merchant apps as incompatible with the terms and conditions for integrating Apple Pay in their apps.
This comes after Google seeks to allay EU antitrust concerns and ward off fresh sanctions.
Spotify claimed that Apple's competing music streaming service, Apple Music isn't subjected to regulations.
Google has been fined a total 6.76 billion euros ($7.7 billion) in the last 17 months.
Daimler and BMW want to combine their car-sharing units Car2Go and DriveNow .
Google said it will still present users with photos and prices when they search for products online and offer a purchase link directly.
Under the previous proposal under the EU antitrust investigation, Google had reserved the first two places for its own ads.
EU hits Google with record $2.7 bn antitrust fine, says co denied others chance to compete, innovate
The European Commission said the world's most popular internet search engine has 90 days to stop favoring its own shopping service or face a further penalty of up to 5 percent of Alphabet's average daily global turnover.
Google chief executive Sundar Pichai will meet with the European Union's competition commissioner Margrethe Vestager in Brussels in the coming week, a source familiar with the matter said Saturday.
Two prominent internet companies Yelp and TripAdvisor have found that Google search results on a smartphone for these businesses had started getting buried beneath Google’s own businesses.
Google has hit back at EU antitrust regulators' warning of a possible hefty fine, saying this would be inappropriate because of the unusual nature of the case and its willingness to settle the case with concessions last year.
The European Union's decision to take on Google last week stems from offical complaints by 19 companies in Europe and the United States, including Microsoft and a number of small firms, people familiar with the matter said on Friday.
Google executive chairman Eric Schmidt will meet Europe's antitrust chief next week, two sources with knowledge of the matter said on Tuesday, a move likely to help regulators decide the next step in a four year-old investigation into the Internet company.
Google's latest offer to settle a European investigation into the alleged abuse of its dominant positions in online search and...
Google said on Monday it had done a good job coming up with concessions to allay EU antitrust ...
The European Commission says Motorola Mobility may have abused its dominant market position to deny Apple the right to use technology essential...