We are constantly working to improve overall performance, speed, and scalability of all Bubble applications. In the meantime, we recommend that you check out these forum posts for Bubble's best-practice advice when it comes to app performance.
If your app is on a Legacy plan (Personal, Professional, or Production), we also recommend that you check your application’s Logs tab to monitor your capacity usage by using the Capacity Usage pie chart to see which workflows and actions are using up the highest volume of your application’s capacity. You can also use a capacity boost from the App Plan tab in the Settings menu to see if additional capacity would help your application run more smoothly.