Open zet4u once with internet, and it keeps working without it. While you browse, the site quietly saves its pages, tools, games and data on your device. On a plane, underground, in the mountains or abroad without data, everything that has been saved keeps working.
What works with no internet
- every calculator and converter;
- the currency converter, with the last exchange rates it saved (it shows their date);
- every game against the computer, and two players on one device;
- the guides, explanations and examples on every page.
What needs internet
- playing with a friend on another phone – their moves have to travel to you;
- getting the newest exchange rates and figures – the saved ones are used until you are back online;
- the very first visit, when the site saves itself.
How it gets onto your phone
- Open zet4u with internet and use it – tap, scroll or type. A few seconds later it starts saving itself in the background; the badge above shows the progress.
- When it says “Ready: works offline”, you can switch on airplane mode.
- When you are back online, it checks for new pages and data at most every six hours and downloads only what changed.
On mobile data, or with data saver on, it does not start on its own: tap the badge to start it.
Install it as an app
Installing zet4u puts an icon on your home screen and opens it without the browser bar. It is also the surest way to keep the offline copy: on iPhone and iPad, Safari can clear the saved data of a site you have not visited for about a week, but not of an installed app.
- iPhone and iPad (Safari): tap the Share button, then Add to Home Screen, then Add.
- Android (Chrome): tap the menu (⋮), then Install app or Add to Home screen.
Private and light
The offline copy lives only on your device; nothing about you is sent anywhere. It takes a few megabytes, and you can remove it at any time by clearing this site's data in your browser settings.