The fastest way to make your app feel faster isn't optimization. It's optimistic UI.
Update the screen instantly, sync in the background, roll back if it fails. Users perceive speed from the interface responding, not from your actual latency. Changed how my whole app feels in an afternoon.
The biggest lever for my retention wasn't a feature. It was the empty state.
New users opened to a blank screen and 70% never came back. I added one pre-filled example and a single line of copy explaining what to do next. Retention doubled. No new code, just less confusion.
Look at your empty states. First thing every user sees, usually the last thing we design.
What's the smallest thing you've launched that actually made money?
Trying to convince myself I don't need 6 more months of features before charging anyone.