The news: Shopping held the No. 1 spot in US app advertising spending in January, per Sensor Tower data, but gaming is on the rise. Data from the first month of 2026 could be a predictor for full-year ad spend.

• Shopping held the highest share of ad spend (16.4%), but that share dropped 8.4% YoY.
• Health and wellness holds the No. 2 spot at 12.3% share, growing slightly YoY. This category tends to peak in January and then drop to third place the rest of the year.
• Gaming rounds out Sensor Tower’s top six at just 8.1% of ad spend, a 42% YoY increase for the category. While its share is low, the jump indicates a promising outlook for advertising within the category.
• Meanwhile, financial services apps leapfrogged CPG to reach the No. 3 spot in ad spend.

Why it matters: A changing mix in app ad spend should follow audience reach. We forecast 53.8% of the US population will use mobile app games this year, on par with US mobile shopping app users.

Considering shopping apps garner twice as much ad spend as gaming apps for the same audience size, the latter offers a clear opportunity for advertisers to capture comparable reach at a relative discount.

The challenge: GenAI advertising is a wild card for 2026.

• OpenAI’s addition of ads beneath ChatGPT responses in free and Go plans could reshape the field this year. It’s testing ads now but plans a full rollout this month.
• Its plan to use view-based pricing versus clicks could challenge current measurement models.

US time spent in AI assistant apps grew 411% YoY in October, and ChatGPT US in-app purchase revenues increased 185% YoY, per Sensor Tower. That wide audience and willingness to spend will likely boost ad spend and ad revenues in the genAI category.

Recommendations for advertisers: Focus budgets on less saturated markets with considerable audiences to boost opportunities for engagement.

• Gaming apps: Deploy rewarded video or billboard in-game ads to maximize reach and attention. Consider partnerships for in-game experiences.
• Shopping apps: Home in on preferred demographics and specific audiences, and deploy AI to serve ads that feel personal to users.
• GenAI apps: The cost of entry for ChatGPT’s beta ad testing is high ($200,000 commitments), limiting it to large brands. Monitor metrics within that space to determine if the expense is worth it.