ABOUT
About SpyglassBeacon
SpyglassBeacon is a day counter for people whose tax residency depends on where they physically were. It runs quietly in the background on your iPhone, counts your days in every US state and country automatically, and warns you before you cross a line like a state 183-day rule or the Schengen 90/180 limit, so you can prove where you were if a tax authority ever asks.
It is built by PerfSpot LLC, a small team that makes a handful of independent, single-purpose tools. We are not a big platform with one login and a shared account. Each tool stands on its own and solves one problem well. SpyglassBeacon exists because tracking residency days by hand, from calendars and passport stamps, is exactly the kind of tedious, error-prone job software should just do for you, privately and on your own device.
The tools below share builders with SpyglassBeacon. Think of them as relatives rather than a product suite: separate apps that happen to come from the same workshop, linked here where one might genuinely be useful to you.
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