New Delhi, Feb 7 : Despite app store privacy changes by Apple and Google that are hitting advertisers, global digital advertising spend will increase from $407 billion in 2022 to $753 billion in 2026 -- an 85 per cent growth and driven by in-app growth, a new report showed on Monday. Although privacy changes from Apple and Google are restricting the potential for effective ad attribution, there are still major opportunities. The mobile in-app revenue will account for 56 per cent of global spend by 2026, according to Juniper Research. The report predicts that total mobile in-app advertising spend will increase from $201 billion in 2022 to $425 billion in 2026, as brands strive to secure consumer trust. "With recent data collection policy changes by technology giants creating further challenges for mobile attribution, enterprises must adopt a code of best practice to maximise return on advertising spend and support probabilistic attribution models," said research author Scarlett Woodford. Apple iOS privacy changes will cost Meta (formerly Facebook) a whopping $10 billion in 2022, the social network has forecast. According to the report, in order to optimise opt-ins, enterprises must "clearly outline their data collection, storage, and usage policies". When it comes to desktop advertising, the spending will increase from $97 billion in 2022 to $142 billion in 2026, despite a diversion of spend towards handheld devices and the implementation of data protection regulation impacting cookie policies. The research identified video as a key channel for advertisers, with video ad spend expected to grow by 63 per cent over the next four years. The success of TikTok and YouTube Shorts continues to drive demand for video advertising and justify premium charges, said the report. /IANS