Rock tumbling is magical — but it takes weeks, and it's easy to forget which stage you're on or when it's time to change the grit. Otter Rock Tumbler Timer keeps a friendly countdown for every tumbler you own and taps you on the shoulder exactly when each step is done, so your rocks come out beautifully polished and nobody has to babysit the calendar. Made for families and hobbyists, it turns the long wait into a fun adventure you can watch unfold. WHAT YOU CAN DO • Track as many tumblers as you like — each one runs its own batch of rocks. • Follow the four grit stages (Coarse, Medium, Fine, Polish) with a live day-by-day countdown. • Get a reminder the moment a stage finishes, so you always know when to switch grit. • Forgot to hit Start? Adjust the start time and the timer catches right up. • Snap up to five photos per batch — from the rough "before" stone to the final shiny gem — and watch your rocks transform. • Build a growing Collection of every rock you've polished. • Use "Identify My Rocks" to gather your photos into a ready-to-share prompt for an AI helper that can guess the rock type, where it's found, and what it might be worth. PRIVATE BY DESIGN • No accounts, no sign-ups, no ads, no tracking. • Everything stays on your device — your tumblers, timers, and rock photos are yours alone. Whether you're a kid with your first tumbler or a seasoned rockhound running several at once, Otter Rock Tumbler Timer keeps the whole journey on track — all the way to shiny.