Global app engagement experienced a significant upward trend between 2018 and 2021, catalyzed by the COVID-19 pandemic. Monthly active users (MAU) for the top 500 apps grew at a compound annual growth rate of 12 to 14 percent, with the average top app gaining approximately 10 million MAU annually. While a spike in engagement occurred during 2020 lockdowns, growth rates and time spent largely normalized by the second quarter of 2021, though they remained above pre-pandemic levels. The analysis covers worldwide usage on iOS and Android across various categories and game genres. Business, Education, and Medical apps emerged as the fastest-growing categories due to shifts in remote work and remote learning. Conversely, Travel and Navigation suffered the most significant declines, though they began a slow recovery as restrictions lifted. In the gaming sector, Hypercasual titles dominated MAU and weekly active user metrics, while the Shooter genre led in daily active users. Engagement depth varies significantly by category and platform. Social Networking apps see the highest frequency of use, averaging nearly 10 sessions per day on Android, whereas Entertainment apps lead in daily time spent at approximately 30 minutes. Within gaming, mid-core genres like Strategy and RPG command the highest engagement, with users averaging about one hour of play per day. A strong correlation exists between time spent and revenue per download, particularly in mid-core and Casino genres. Retention trends reveal a divergence between games and non-games. While non-game retention improved during the study period, overall game retention—specifically day 30 metrics—was dragged down by the proliferation of Hypercasual titles, which prioritize high user acquisition over long-term loyalty. Tabletop games remain an outlier in the gaming category, maintaining the highest long-term retention and daily time spent among casual genres. Data for this analysis was sourced from Sensor Tower’s Usage and Store Intelligence platforms, benchmarking the top 100 to 500 apps per category.