Cliff Timer vs BellAlert

Cliff Timer is a simple and powerful app that lets you measure real-world distances using just a stopwatch and basic physics. By timing how long it takes for an object to fall, you can estimate the height of cliffs and other drops, or measure how far away a storm is by counting the seconds between lightning and thunder. Designed to be easy to use while still based on real equations, Cliff Timer turns quick observations into meaningful measurements, making it perfect for outdoor exploration, learning, or satisfying your curiosity about the world around you. This app uses the formula for height, h=12⋅g⋅t^2, and the formula for lightning, d=t/5. Start the stopwatch, and the app will give you the information.

Some notifications matter more than others. Bell Alerts lets you give each one its own sound — so you know what just happened without even looking at your phone. Create a bell, share its code, and ring it. Everyone you've shared it with gets the alert instantly — each on their own phone, with the sound they picked. Dinner's ready, the dog's at the door, the meeting's starting: make it a bell. MAKE IT YOURS • A different sound for every bell — a dozen original tones to choose from • Per phone: you pick your sound, your family picks theirs • Vibrate-only or mute any bell, anytime • 11 app icons to match your style SEND A BELL IN A TAP • Create a bell — it gets its own private, unguessable code • Share the code; anyone who adds it is subscribed • Ring it from the app — or straight from a Home Screen widget, without opening anything • Changed your mind? "Oops" un-rings it — the alert crosses itself out everywhere STAY ON TOP OF IT • Recent rings at a glance, with timestamps — canceled ones clearly marked • A Home Screen widget shows the latest bells the moment they ring • Disappearing alerts tidy themselves up after a time you set PRIVATE BY DESIGN • No account, no sign-up, no tracking • Bells are private codes — only the people you share them with get the rings • Verified on device with App Check; standard encryption only FOR POWER USERS Bell Alerts can also receive alerts from your own internet server — the same bring-your-own-server idea as the open-source app ntfy. Send a notification from any script or service you run and it arrives as a custom bell on every subscribed phone. It's a software integration over the internet; no extra hardware or accessory is involved. Setup guide included. Make every alert sound like what it is.