Take Time Zone Buddy with you
See what time it is in any city, convert a date and time across countries, and find the best meeting slot for people in different time zones, from your Android phone, iPhone or iPad. There is no account: your favourite cities and working hours stay on your device. Daylight saving changes are handled automatically.
Android Version 1.0.0
Needs Android 8.0 or newer. Installs like any app and opens straight into Time Zone Buddy.
Scan with your Android phone to open this page there, then tap Download.
Install the APK
- Open this page on your phone and tap Download APK.
- When Android asks, allow installs from your browser (Settings → Install unknown apps), only for this one install.
- Open the downloaded file and tap Install, then Open.
- Pick your cities and working hours. They are saved on this phone, no sign-in needed.
No download? Install from Chrome
Open randomzone.onslate.in/timezone-buddy in Chrome, tap the ⋮ menu and choose Install app (or Add to Home screen). It then opens in its own window and keeps working offline.
Developers: Android Studio project Source
The app is a small, readable WebView shell. Open it in Android Studio, change the address to your own server if you like, and build your own APK or Play Store bundle.
iPhone and iPad App Store: soon
The app builds below need iOS 16 or newer (iPhone and iPad). Apple only allows installing apps from the App Store, TestFlight, or apps you sign yourself, so the options are:
1. Add to Home Screen (works right now, no download)
- Open randomzone.onslate.in/timezone-buddy in Safari.
- Tap the Share button, then Add to Home Screen, then Add.
- Open Time Zone Buddy from your Home Screen. It runs full screen like an app and keeps working offline.
Time Zone Buddy needs no notifications or sign-in, so this is the simplest way to get it on an iPhone. We have not tested it on a real iPhone yet.
Scan with your iPhone camera to open this page in Safari.
2. Build it on your Mac with Xcode Recommended
Free with any Apple ID. Open the project in Xcode, pick your team, plug in your iPhone and press Run. With a free Apple ID the app stays installed for 7 days; a paid developer account removes that limit. Step by step instructions are inside the zip.
3. Unsigned IPA for AltStore or Sideloadly Advanced
This file is not signed, so an iPhone will refuse to open it directly. Sideloading tools such as AltStore or Sideloadly re-sign it with your own Apple ID and install it. It has not been tested on a real iPhone, so if it misbehaves use the Xcode project above.
4. TestFlight and the App Store Coming soon
Publishing needs a paid Apple Developer Program membership (USD 99 a year) owned by the publisher. Until then the options above are the way in.
Chrome extension for your team Version 1.0.0
Made for sales and support teams who book calls across countries. Click the toolbar icon for live clocks, paste a phrase like "3pm PST" to see it in every city you work with, or select a time on any web page, right-click and choose Convert with Time Zone Buddy. The Meet tab suggests the best call slots and copies a ready-to-send summary. It works offline, needs no account and sends nothing anywhere: your cities and working hours stay in your Chrome profile (and sync across your own Chrome devices if sync is on).
Install it in Chrome (about a minute)
- Download the zip above and unzip it into a folder you will keep, for example Documents/TimeZoneBuddy.
- In Chrome open chrome://extensions and switch on Developer mode (top right).
- Click Load unpacked and choose the unzipped folder.
- Click the puzzle-piece icon in the toolbar and pin Time Zone Buddy. Shortcuts: Alt+Shift+T opens it, Alt+Shift+C converts the selected text.
It also works in Edge, Brave and other Chromium browsers the same way. It is not on the Chrome Web Store yet, so Chrome may show a "developer mode" reminder at start-up; keep the folder in place, because Chrome loads the extension from it. To update, download the new zip, replace the folder contents and press the refresh icon on the extension card. The extension asks only for permission to store your settings, add the right-click menu and show the result on the page you click it on, and never reads your pages otherwise.
Questions
What is different from the website?
The app shows the same Time Zone Buddy inside a native window with its own icon, a retry screen when you are offline, and file saving for calendar (.ics) downloads. It is the same web app, so the app, the website and the installed web app all behave the same.
Where are my favourite cities and working hours stored?
Only on the device you use, in the app or browser storage. There is no account and nothing is uploaded, so a different phone or browser starts fresh. Clearing the app's data or uninstalling it removes them.
Does it work offline?
Yes, once it has loaded at least once. The clocks, converter and meeting planner all run on your device using its built-in time zone database, so they keep working without a connection. The app shows a retry screen only if it cannot load the first time.
How do the share links work?
The share option creates a short text summary of the meeting time in every city, an .ics file for your calendar, and a link that opens Time Zone Buddy with the same cities and time already set. The link holds only city names and the time, nothing personal.
Are daylight saving changes handled?
Yes. Times come from your device's built-in time zone database, which knows when each place changes its clocks, now and in future years. Keep your phone or browser up to date so it has the latest rules.
Is there a Google Play or App Store listing?
Not yet. Publishing needs a Google Play developer account and an Apple Developer Program membership, both paid and owned by the publisher. When the listings exist, the buttons on the Time Zone Buddy page switch to the official store links.
Does the Chrome extension see my browsing?
No. It has no access to your pages. It only runs on the page you right-click a selection on, at that moment, to show the converted times, and it makes no network requests. Your cities and hours are stored in your Chrome profile.
How do I remove the app?
Uninstall it like any app. Because nothing is stored on a server, there is no account to delete.
How do I check that a download is genuine?
Each download lists its SHA-256 fingerprint. On a computer run shasum -a 256 <file> and compare the result.