Most visitors can spend 90 days in the Schengen Area in any rolling 180-day period, and counting that window by hand goes wrong easily. Country Days Tracker: Geostay does the count on your iPhone.

It records the days you spend in each country automatically. The Schengen card shows the days you have used, the date you have to leave by, and the day your full 90 days are back. You can add your visa or residence permit to the card with its validity dates and number of entries. A notification tells you ahead of time, for example “Staying past 4 Dec would cross the limit”.

The same record feeds other counters: the UK Statutory Residence Test, the US Substantial Presence Test, visa and residence clocks for 40 countries, and tax residency day tests for 184 countries. You can also add your own rule for any country.

Geostay needs no account, and the travel history stays on the iPhone. https://getgeostay.com