Apps that work without the internet
Northcell makes small, fast Android apps for the things people actually do offline — solving a puzzle on the metro, working out a loan repayment, planning a monthly investment. No accounts, no sign-up, and nothing about you leaves your phone.
Every Northcell app follows the same three rules. It works with aeroplane mode on. It keeps your data on your device, never on a server. And it stays small and quick to open, because a calculator or a puzzle should never make you wait for a network. Apps are free with a single light banner ad, and a one-time purchase removes ads for good — there is no subscription and nothing to renew.
Our apps
Kakuro – Logic Puzzles Offline
A number-crossword with five difficulty levels, a fresh daily puzzle, and hints that teach the next logical step rather than just filling in a square. Every puzzle is verified to have exactly one solution.
EMI Calculator – Loan, GST, SIP & Tax
A suite of India-focused calculators in one offline app: loan EMI with part-prepayment, SIP and lump-sum returns, FD and RD, GST, and an income-tax regime comparison — every figure computed exactly.
Learn something while you're here
Our guides explain the ideas behind the apps in plain language — and they stand on their own whether or not you ever install anything.
- How to play Kakuro: rules and solving techniques
- How a loan EMI is actually calculated
- SIP explained: how monthly investing compounds
Why offline
Most phone apps assume a fast, always-on connection and quietly send your activity to a server. We think a puzzle and a calculator have no business doing either. Building offline-first keeps the apps fast, keeps them working on a train or a flight, and — because there is no backend — means there is simply no copy of your data anywhere but your own device. You can read exactly what each app does, and does not do, in its privacy policy: Kakuro, EMI Calculator.
Contact
Questions, feedback, or a privacy request: hello@northcell.app. We read everything sent here.