DIGITCA vs SurvivalKnife

A tape calculator that doesn't forget. Every number you tap goes onto a tape you can scroll, edit, save, and come back to. No more wiping the screen by accident and losing the whole calculation. No more squinting at one line of digits, trying to remember what you were even working on. DIGITCA is built around a simple idea: numbers deserve a paper trail. The tape isn't just a log. It's the calculator itself. Tap any number to change it on the spot and watch the totals update live. Strike a row out like a pencil would. Undo anything: a deleted row, an edit, even a cleared tape, with a button, a shake, or a three-finger swipe. Autosave keeps your work safe between sessions. FREE Full tape calculator: persistent, scrollable, autosaved, with full undo Editable tape: tap any number to change it and totals recalculate instantly Tape order your way: authentic (newest at the bottom) or modern Cashier mode for quick running totals Scientific keyboard: trig, log, factorial, combinations, permutations, scientific notation, and statistics computed over your actual tape Natural input: type or dictate "twelve fifty plus tax" and DIGITCA gets it. On Apple Intelligence iPhones, an on-device language model catches phrasing the parser can't Date and time math: add days to a date, subtract weeks, calculate durations Currency converter: 161 world currencies + major crypto, rates from open.er-api.com Unit converter: length, weight, temperature, volume, speed, and more Live totals in the Dynamic Island while you calculate Plain text export Default light and dark themes Interactive Home Screen widget Speaks 11 languages, starting in yours DIGITCA FULL Tape archive: name, browse, search, tag, and reload past sessions, synced through your own iCloud, locked behind Face ID or PIN if you want Share tapes as encrypted .digitca files that preview right in the Files app Palettes inspired by classic calculator design: Braun-style, Pixel Art, Blueprint, Swiss, and more Tactile sounds inspired by classic calculators Full export suite: thermal card, PDF, CSV, Markdown, and 9:16 video for Reels and Stories More visual customisation: custom app icon, numeric font packs, tape density, custom logo on exports One-time purchase. Family Sharing supported. INTERACTIVE HOME SCREEN WIDGET Pin a live currency converter to your Home Screen. Tap to swap currencies, switch between preset amounts, and see the unit rate and last update time at a glance. NO SUBSCRIPTIONS. NO ADS. NO TRACKING. Your tapes live on your device and sync only through your own iCloud. We have no servers, no accounts, and no idea what you calculate. For shopkeepers, accountants, cooks, freelancers, designers, students, and anyone who runs the same numbers more than once and wants to remember how they got there. Made in Brevnov, Prague.

Most emergency advice is written for a generic family that doesn't exist. SurvivalKnife builds a plan around the people actually in your home - their medications and mobility needs, your pets, your dwelling, your vehicles - and it keeps working when the cell network doesn't. A PLAN FOR YOUR ACTUAL HOUSEHOLD Answer a few questions and SurvivalKnife writes a plan specific to you: who lives there, what they need, and the hazards where you live. Every plan comes with an action checklist you can tick off, attach photos to, and print. Seven ready-made plans - flood, wildfire, hurricane, earthquake, tornado, power outage and more - work instantly and offline. Personalize any of them to make it yours. When something isn't on file, the plan asks you instead of guessing. OFFLINE MAPS AND OFFLINE ROUTING Download the states you care about and get a real map with turn-by-turn routing and no cell service at all. The routing engine runs on your phone, not in the cloud. Layers for shelters, hospitals, fire and police, and water stay available offline, plus cellular coverage maps so you know where you'd get a signal. KNOW WHAT YOU HAVE - AND WHAT'S MISSING Scan a shelf with your camera or add items by voice. SurvivalKnife scores your readiness against real scenarios and shows the next most important gap to close. The needs calculator does the math for your household: calories, water, sanitation and days of supply, adjusted for climate and activity. ONE PLAN, EVERY PHONE IN THE HOUSE Family Edition covers up to 5 people. Plans, saved materials, routes, inventory and your household profile stay in sync on everyone's phone. Younger members get Youth View - a simplified version that shows only what a guardian has approved for them. HOUSEHOLD RECORDS, READY WHEN YOU NEED THEM Printable medical and contact wallet cards. Blood types, medications, allergies, mobility needs, key contacts, addresses with dwelling details and vehicles - all in one place, all feeding your plans. A PRIVATE VAULT THAT STAYS ON YOUR PHONE Passports, insurance, IDs. Vault items stay on your device, never sync to your household, and are excluded from AI and search. Set a vault PIN to encrypt them. KNOW WHAT'S HAPPENING NEAR YOU Wildfire detections, weather warnings, air quality and earthquakes on the map, with notifications for the ones near your home. LEARN BEFORE YOU NEED IT A two-minute daily survival lesson with streaks and skill paths, plus an offline field guide covering water, first aid, shelter and navigation - readable with no connection. PRIVACY Your Personal Vault never syncs - not to us, not to your household - and setting a vault PIN encrypts it on your device. Household details shared with AI to build a plan are minimized: first names only, never phone numbers, emails or addresses. Maps and routing run on your phone. No ads. No data sold. SUBSCRIPTION Start with a 14-day free trial of everything. Then Field Edition is $19.99/year for one person, or Family Edition is $39.99/year for a household of up to 5 - about 67 cents per person per month. Everything you set up during the trial is saved. Subscriptions are billed annually to your Apple Account and renew automatically unless canceled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple Account settings. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://survivalknife.ai/privacy IMPORTANT SurvivalKnife is a preparedness and educational reference tool. It is not a substitute for professional training, qualified medical care, or emergency response services. It does not contact emergency services, monitor your location, or alert anyone on your behalf. In any actual emergency, call 911 or your local emergency number.