Microsoft To Do supported versions by device
Microsoft To Do still runs on Windows, macOS, iPhone, iPad, Android, and the web, but only when your device and app version are still supported. In practice, that means a current enough operating system, an app build from the app store or browser that Microsoft still allows, and a sign-in flow that still works on that platform. If your phone or computer is several OS generations behind, the app may still install but refuse to sign in, stop syncing, or lose features.
What Microsoft To Do actually supports right now
Microsoft To Do supports Windows, macOS, iPhone, iPad, Android, and the web app. On Windows and macOS, support depends on both the operating system and the app package you install. On mobile, it depends on the phone or tablet OS version and the version of Microsoft To Do from the App Store or Google Play. If you are checking for work use, your organization’s sign-in rules can also block access even when the device itself is supported.
For example
Say you install Microsoft To Do on an older iPhone. The app might still appear in the App Store, but if the iPhone’s iOS version is too far behind, sign-in or sync can fail even though the app is present. The same pattern can show up on older Windows PCs, Macs, and Android devices.
The versions people usually need to check first
Microsoft does not always publicize a single, permanent minimum version in the app itself, so the practical check is to compare what you have installed against the current store listing or Microsoft support page for the platform you use. The two things to check are the app version and the device operating system version. If either one is too old, that is where support usually falls apart. A device can look fine on paper and still have trouble if the app store no longer offers updates for it or the browser is too old for the web version.
What breaks when your version is too old
The version limits usually show up first in sign-in, sync, or install problems. If Microsoft To Do will not install, your device is probably below the app’s current OS requirement or the store no longer supports that device. If the app opens but won’t sign in, the problem may be an unsupported OS, an old app build, or an account rule from your organization. If one device stops syncing while the others still work, the age of that device is often part of the answer. If the problem shows up everywhere, the issue is more likely account-related, service-related, or tied to a recent app update.
How to check your Microsoft To Do version in a minute
Start with the app version and the device OS version. On phones and tablets, open the app store listing for Microsoft To Do and compare the installed app with the current listing. On Windows and macOS, check the version number in the app and compare it with Microsoft’s current requirements for that platform. For the web app, use a current browser and make sure the browser itself is updated. If you need a quick comparison and do not want to hunt through menus, the store listing is usually the easiest place to see the current app version requirement. The device OS version is the other half of the check, especially on older phones and older Macs or PCs.
What to do if your device is no longer supported
If your device is too old, the safest workaround is usually the web version on a newer browser, even if the old device can no longer run the app. If the browser on that device is also too old, move the task list to a newer phone, tablet, or computer before you depend on it. If you need to keep using the old device for a while, treat Microsoft To Do as unreliable on it and avoid making it your only copy of your task list. If the store will not update the app or the OS can no longer be updated, the device is probably past the point where Microsoft To Do is a dependable choice.
Conclusion
If you are deciding whether to rely on Microsoft To Do, check three things: your device’s operating system, the app version, and whether the web version works in a current browser. If all three are current, you are usually fine. If your device is old enough that the store will not update the app or the OS can no longer be updated, switch to the web app or move your task list to a newer device before you depend on it.
Frequently Asked Questions
Does Microsoft To Do still work on older phones?
Sometimes, but not reliably once the phone’s operating system is too far behind. An older phone may still open the app, yet sign-in or sync can fail if the OS is no longer supported.
Can I use Microsoft To Do in a browser instead of the app?
Yes. The web app is often the best fallback if the desktop or mobile app is not supported anymore, as long as your browser is current enough.
Why did Microsoft To Do stop syncing on one device only?
That usually points to a version problem on that device, such as an outdated app, an unsupported OS, or a browser that is too old for the web app.
Do I need the newest version of Microsoft To Do?
You do not always need the newest build immediately, but you do need a version that Microsoft still supports. If updates are available, installing them is usually the safest choice.