To answer your first question; yes, it's possible to build dynamic apps that can countdown the seconds to zero or build a timer dynamically. The sample application: https://app.appsmith.com/app/input-widget/input-counter-reva... shows a counter. In this example, while a user is required to click a button, this can be modified to be triggered automatically every 1 sec.
It's currently not possible to power the UI via websockets yet. This is an open feature request that we are yet to implement.
Having said that, I'm sorry that Appsmith crashed for you. Were you trying us out on Appsmith Cloud (https://app.appsmith.com) or were you self-hosting Appsmith via Docker/k8s?
Please feel free to email me at arpit [at] appsmith.com & we'll help you out succeed with the product.
