#1MinuteTip #SalesforceSpring21 Performance Analysis in App Builder now assesses record page performance for the phone form factor. New tabs in the Page Analysis window give you separate results for a Lightning record page when it loads on a desktop and on a phone so you can design your page for optimal performance on both.
![Lightning Pages Performance](https://amazon.asagarwal.com/images/2021_02_16_lightning_app_builder_performance_analysis_phone_form_factor.png)
References & Useful URLs
- Salesforce Spring ’21 Release Note Article – Analyze Performance For Lightning Pages Viewed on a Phone