About
About Residay
Residay is a privacy-first iPhone app that records which country you are in each day and evaluates your presence against tax-residency, visa and citizenship day-count rules. It computes what is computable, captures the rest as explicit attestations, and never issues a verdict — it reports rule conditions with an evidence trail.
Why it exists
People whose residency depends on day counts are usually tracking them in a spreadsheet assembled from memory, boarding passes and passport stamps. That works until someone asks for evidence — and by then the year is over and the detail is gone. The tests themselves are also less intuitive than they look: the UK counts days you are present at midnight, Cyprus counts your arrival day but not your departure day, the Schengen area counts both, and New York counts any part of a day. A single spreadsheet column cannot be right for all of them at once.
Residay records each day as it happens, applies the correct convention per rule, and keeps the evidence behind every attribution so the count can be explained later rather than merely asserted.
The position on privacy
A record of where you were every day is among the most sensitive datasets a person can hold, so the app has nowhere to send it: no account, no server, no analytics. Its App Store privacy label reads "Data Not Collected", and that is a description of the architecture rather than a summary of a policy. The full privacy position sets out what that does and does not mean.
The position on correctness
Residay maintains 51 researched, versioned rules across 32 jurisdictions, each carrying a link to the responsible authority's own guidance and the date it was last verified. Correctness is pinned by 119 golden test vectors that every implementation must reproduce identically.
We publish both the methodology and the rule data itself, because a day counter asking to be trusted with a tax position should be checkable rather than merely confident.
Who makes it
Residay is built in Malta by Maze Digital. Questions, corrections to a rule, or an advisor enquiry: hello@residay.com. Corrections to rule data are especially welcome — every rule carries its source, so a disagreement can be settled by reading it.
Residay does not provide tax or legal advice. It reports rule conditions and the evidence behind them; decisions about your tax position belong with a qualified professional.