--- title: New Changes Coming to Sessions and User Engagement in... description: Google Analytics for Firebase changed how sessions and user engagement are measured. Sessions now start immediately (no 10-second foreground delay) instead of... canonical: https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: New Changes Coming to Sessions and User Engagement in Analytics | daily.dev og:description: Google Analytics for Firebase changed how sessions and user engagement are measured. Sessions now start immediately (no 10-second foreground delay) instead of... og:url: https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj og:image: https://api.daily.dev/og/posts/8MlAGFgPj.png og:image:alt: New Changes Coming to Sessions and User Engagement in Analytics og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # New Changes Coming to Sessions and User Engagement in Analytics **[Firebase](https://daily.dev/sources/firebase-blog)** · 6 min read · 0 upvotes · 0 comments ## Summary Google Analytics for Firebase changed how sessions and user engagement are measured. Sessions now start immediately (no 10-second foreground delay) instead of requiring 10 seconds in foreground, and a new extend_session parameter along with ga_session_id and ga_session_number event parameters make session-based BigQuery analysis much simpler than the old manual grouping approach. User engagement tracking also changed: instead of separate user_engagement events, an engagement_time_msec parameter is added directly to events like screen_view, first_open, and app_exception starting in early 2019, requiring BigQuery queries to be updated to filter on that parameter rather than the user_engagement event name. An update note confirms the engagement_time_msec change actually launched in April 2020, later than originally planned. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How does session_start triggering change in the new Firebase Analytics SDK compared to before? The new Firebase SDK removes the 10-second foreground delay, triggering session_start as soon as the app enters the foreground instead of waiting for 10 seconds of foreground time. Previously, Google Analytics for Firebase only fired session_start if there was no current session and the app stayed foregrounded over 10 seconds; now that delay is gone entirely. _daily.dev helps mobile developers track SDK behavior changes like this before they ship an analytics update._ ### How do I calculate average events per session in BigQuery using Firebase Analytics data now that ga_session_id exists? Group events by the ga_session_id parameter instead of manually reconstructing sessions from timestamps and pseudo_user_id gaps. For example, count events per session_id extracted from event_params, then average those counts across sessions using a subquery with GROUP BY session_id and HAVING session_id IS NOT NULL. _Developers refining BigQuery analytics queries can follow schema changes like this on daily.dev._ ### Why did my Firebase BigQuery query for user_engagement time become inaccurate after the analytics update? Firebase stopped sending separate user_engagement events for tracking engagement time and instead started adding an engagement_time_msec parameter directly to other events like screen_view, first_open, and app_exception, starting in early 2019 with the feature actually launching in April 2020. Queries filtering only for event_name equal to user_engagement will undercount, so queries should instead filter for any event containing engagement_time_msec greater than zero. _daily.dev keeps analytics engineers from being blindsided when a vendor changes event schemas mid-migration._ ## Similar posts on daily.dev - [Introducing BigQuery Agent Analytics](https://daily.dev/posts/introducing-bigquery-agent-analytics-9cxicqkzb) · Google Cloud · 1 upvotes · 0 comments - [Conversational Analytics in BigQuery now GA](https://daily.dev/posts/conversational-analytics-in-bigquery-now-ga-o1nti3zgs) · Google Cloud · 0 upvotes · 0 comments --- Tags: [#firebase](https://daily.dev/tags/firebase), [#google-bigquery](https://daily.dev/tags/google-bigquery), [#google-analytics](https://daily.dev/tags/google-analytics) [View this post on daily.dev](https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"New Changes Coming to Sessions and User Engagement in Analytics","url":"https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj"},"datePublished":"2026-08-23T12:19:20.764Z","dateModified":"2026-08-23T12:36:15.705Z","description":"Google Analytics for Firebase changed how sessions and user engagement are measured. Sessions now start immediately (no 10-second foreground delay) instead of...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/7ed721de96163685d26ab7e314be3ebc?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/7ed721de96163685d26ab7e314be3ebc?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Firebase","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Firebase","logo":"https://media.daily.dev/image/upload/s--i395oqZH--/f_auto,q_auto/v1787487448/logos/firebase-blog?_a=BAMAMicg0","url":"https://daily.dev/sources/firebase-blog"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"firebase,google-bigquery,google-analytics","timeRequired":"PT6M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Firebase","item":"https://daily.dev/sources/firebase-blog"},{"@type":"ListItem","position":3,"name":"New Changes Coming to Sessions and User Engagement in Analytics"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/new-changes-coming-to-sessions-and-user-engagement-in-analytics-8mlagfgpj#faq","mainEntity":[{"@type":"Question","name":"How does session_start triggering change in the new Firebase Analytics SDK compared to before?","acceptedAnswer":{"@type":"Answer","text":"The new Firebase SDK removes the 10-second foreground delay, triggering session_start as soon as the app enters the foreground instead of waiting for 10 seconds of foreground time. Previously, Google Analytics for Firebase only fired session_start if there was no current session and the app stayed foregrounded over 10 seconds; now that delay is gone entirely. daily.dev helps mobile developers track SDK behavior changes like this before they ship an analytics update."}},{"@type":"Question","name":"How do I calculate average events per session in BigQuery using Firebase Analytics data now that ga_session_id exists?","acceptedAnswer":{"@type":"Answer","text":"Group events by the ga_session_id parameter instead of manually reconstructing sessions from timestamps and pseudo_user_id gaps. For example, count events per session_id extracted from event_params, then average those counts across sessions using a subquery with GROUP BY session_id and HAVING session_id IS NOT NULL. Developers refining BigQuery analytics queries can follow schema changes like this on daily.dev."}},{"@type":"Question","name":"Why did my Firebase BigQuery query for user_engagement time become inaccurate after the analytics update?","acceptedAnswer":{"@type":"Answer","text":"Firebase stopped sending separate user_engagement events for tracking engagement time and instead started adding an engagement_time_msec parameter directly to other events like screen_view, first_open, and app_exception, starting in early 2019 with the feature actually launching in April 2020. Queries filtering only for event_name equal to user_engagement will undercount, so queries should instead filter for any event containing engagement_time_msec greater than zero. daily.dev keeps analytics engineers from being blindsided when a vendor changes event schemas mid-migration."}}]} ```