The announcement in a Wednesday blog post by the Alphabet
unit comes shortly before Apple is expected to start enforcing new tracking
transparency rules.
Apple for years has supplied apps with a unique identifier,
known as IDFA, to help them link the same user across multiple programmes. The
code can be essential in determining to whom to show an advertisement and
tracking whether it prompted them to make a purchase.
But Apple has said that early this year it will require that
apps show users a one-time pop-up message to gain their consent to access their
IDFA.
Facebook and other app makers are concerned the warning may
discourage users from opting in and cripple advertisement sales.
As users of Google's apps are typically logged in, it has a
tracking alternative to IDFA and as such its core advertisement business would
likely not be affected by Apple's changes.
But it warned in its blog post that publishers and
advertisers that rely on its mobile advertisement software will experience
weaker results without IDFA access.
Google said it is developing alternatives for clients but
these may not be ready immediately.
Google added that clients can use its software regardless of
whether they show the pop-up and obtain the necessary consent, and it is not
making any recommendations on what they should do.
Apple said apps not using IDFA still are required to seek
user permission if they show and measure advertisements based on data acquired
from other companies.
To comply, Google said its iPhone apps will stop using data
from so-called third parties to personalise advertisements.
Facebook said last month that it plans to display the pop-up
to seek users' consent.
"Apple has made it clear that if we don't use Apple's
prompt that they will block Facebook from the App Store, which would only
further harm the people and businesses that rely on our services every
month," it said.
© Reuters