DIGITCA vs Air Gap Transfer

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.

Air Gap Transfer moves a file from one phone to another using nothing but the screen and the camera. One device turns your file into a moving pattern of codes. The other points its camera at that screen and rebuilds the file as it watches. No Wi-Fi, no Bluetooth, no cable, no cloud, no account, and no pairing. WHY Sometimes the network is the problem. You are on a locked-down guest Wi-Fi. AirDrop is disabled by policy. The other phone is on a different platform. The machine you are working with is deliberately kept off every network. Or you simply do not want a copy of your file passing through somebody else's server. Air Gap Transfer needs none of that infrastructure. If the two devices can see each other, they can talk. BUILT TO SURVIVE A SHAKY HAND Holding a phone perfectly still for a minute is not realistic, so the app does not ask you to. The file is spread across the stream with error correction, and the receiver keeps whatever it catches. Miss a fifth of the frames to blur, a passing hand or a glance away, and the transfer still completes. Nothing has to be sent twice and nothing has to be restarted. Every recovered file is checked against four separate checksums before it is offered to you. If it does not match exactly, you are told, rather than handed a quietly corrupted file. NOTHING LEAVES YOUR DEVICE There is no server to leave it to. The app has no networking code at all. Your files are read, encoded and displayed entirely on your own phone. The camera sees frames, decodes them in memory and discards them; nothing is recorded. HONEST ABOUT SPEED This is light travelling between two screens, not a network. Expect a small document or photo rather than a video library — files are capped at 32 MB, and a megabyte takes around a minute. For anything that fits, it works anywhere, including places nothing else does. A companion web version lets a laptop act as either end.