When Apple launched a sweeping iPhone privacy change last year, it spelled trouble for the entire online ad industry, including companies that help advertisers and app developers measure whether mobile ads prompted consumers to make purchases.

Facebook owner Meta Platforms and other ad sellers took a hit, but the intermediaries that measure mobile ad performance managed to get by with tactics that included developing new systems to offset some of what Apple’s changes took away from them.

For instance, Kochava, an 11-year-old mobile ad measurement firm, said its revenue last year rose 30%, roughly the same as in prior years. And a rival called Branch said it has raised $300 million in a funding round that increased its valuation to more than $4 billion, up from $1 billion in 2019. The company projects its revenue could double this year from nearly $100 million last year, a person familiar with the matter said.