Looking for a Schedule Management Tool? Try Microsoft Cortana
Only three apps on my phone are allowed to send background notifications: WeChat (Some Simple Tips for Handling Things on WeChat | Tricks for Working with WeChat), QQ Sync Assistant (Managing Your Important Dates, You Can't Go Wrong with It: QQ Sync Assistant | Productivity Tool), and finally this Cortana by Microsoft, which I prefer to call my best assistant.

Why I Recommend Cortana

Seeing this image basically shows what I'm recommending. Just as this widget displays, what I value most about Cortana is its schedule reminder feature. You can set your reminders however you like, according to your own needs.
If you have a regular lifestyle or want to pursue a more structured daily routine, then Cortana is an excellent choice. Although I previously recommended QQ Sync Assistant in the article Managing Your Important Dates, You Can't Go Wrong with It: QQ Sync Assistant | Productivity Tool, that app only handles anniversary reminders. It can't set reminders at specific times, nor can it schedule weekly or daily alerts.
Actually, I've tried many reminder apps, but none were quite ideal. Sticky note tools can record events but can't remind you—if you get busy, you'll forget. Other scheduling apps lack the flexibility to adjust reminders by day or week or to customize event descriptions. While WeChat does have reminder features, they only work after long-pressing text, which is fine for work follow-ups but insufficient for daily life. So I chose Cortana.
Besides that, the three icons in the widget

These three functions are rarely used. The first and third are for editing reminders. (With this widget added, you can comfortably hide Cortana from your home screen and not occupy space with frequently used apps—background notifications will suffice, and you only need to access this widget when editing.) The second icon wakes up the Cortana voice assistant, which I also rarely use. I mainly use this app for its reminder tools. (You can use voice commands to send texts, make calls, open WeChat, QQ, or NetEase Cloud Music.)
(Back when Microsoft was still making Lumia phones, I got a Lumia. The default bottom navigation menu was Cortana, just like in Windows 10 now—the quick launch bar at the bottom had a long Cortana input box, which was quite handy.)

For managing daily schedule events, it covers all my needs. Additionally, once logged into your Microsoft account, reminders sync across phone and computer. This way, even if you're deep in work at your computer, you'll still get notified and won't forget what you're working on.
As shown in the image, it's truly very convenient.
There's also a pleasant surprise—the app's interface looks really nice:

Notice the weather display on the lock screen notification? The weather updates are proactive. As long as you enable background notifications for Cortana, it will push alerts whenever weather data changes. For example, I track Tianjin's weather. When smog gets worse there, I get a notification; when it snows in Changchun in the afternoon, I'm reminded too. (It usually pushes a morning weather forecast around 8 a.m. for your current city. For cities you follow, notifications only come when there's a change—like a sudden temperature drop, rain, or snow. Pretty cool, right?)
And I'm also quite satisfied with the design sense of the app's interface.

There are some other rather trivial features, like traffic restriction info. (These trivial updates don't appear in background notifications, nor do news updates—notifications are limited to reminders and weather changes. Even if Cortana itself gets an update, you'll only know if you open the app; otherwise, you won't be disturbed.) For instance, if you follow movies, recent releases will appear on this screen. (There are also services like package tracking, but they're trivial and I don't use them, so I haven't explored much. My usage scenario is purely for schedule reminders. Once set up, I rarely open the app—the last time was late 2017, and it prompted me to update to the new version.)
I really like Microsoft. Imagine this: use Managing Your Important Dates, You Can't Go Wrong with It: QQ Sync Assistant | Productivity Tool to manage your contacts and date reminders so you never miss important days; use Some Simple Tips for Handling Things on WeChat | Tricks for Working with WeChat to handle simple WeChat tasks, and hand over your daily reminders to Cortana. You definitely won't miss anything important.
(Feel free to submit reviews of useful software or hardware. Write about what you like and find helpful. We welcome any articles related to lifestyle, as we aim to build Guangjian into a lifestyle account: living our preferred little lives, learning from others' ways, and improving the efficiency of our own time.)
I want to show you how beautiful the rest of my life can be.
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