An alternative to KDE Connect is Pushbullet. While the free version has some limitations and it doesn't offer all the features available with KDE Connect, it does provide options to send files up to 25MB, send messages from your desktop (limited to 100/month in the free version, and a storage cap of 2GB) and most importantly, it can mirror your phone's notifications on the desktop.
Note that Pushbullet requires both the Android device and desktop to be connected to the Internet, but they don't have to be in the same network.
Pushbullet Pro (US $3.33/mo if you pay yearly or US $4.99/mo if you pay monthly) offers more features, like universal copy & paste, unlimited messages, send files up to 1GB with 100GB storage space and more.
I should also note that Pushbullet supports both Android and iOS but for the former, notification mirroring is only supported on Mac.
On Linux, Pushbullet can be used with a browser extension, however, if you want to use it as a stand-alone app, you can give PB For Desktop a try.
PB For Desktop is an unofficial open source Electron-based application for PushBullet, available for Linux, macOS and Windows. Among its features are:
- mirror Android notifications on your desktop;
- native desktop notifications;
- configurable sound notifications;
- option to snooze notifications for 1, 4 or 8 hours;
- send and receive SMS using your Android devices from the desktop (with autocomplete for contacts / phone numbers);
- runs as a tray/appindicator;
- simple setup, no need to use API keys, etc.;
- channel-specific icon images for most notifications;
- previews for pushes containing images;
- Pushbullet pro only: universal copy & paste.
Note: PB For Desktop uses native notifications without any dismissible dialog, so you may miss notifications if you're away from the computer. A way to avoid missing important notifications on desktops that support AppIndicators is to use Recent Notifications Indicator.
Download PB For Desktop
Download PB For Desktop - includes binaries for Linux (32bit, 64bit and armv7 deb, rpm, and AppImage), Windows and Mac.
To use it, you'll also need to install Pushbullet (requires signing up) on your Android or iOS (but remember that for iOS, mirroring notifications on your desktop isn't supported unless you're using macOS) device.
As an alternative, you may also want to check out Pushbullet Indicator (hasn't been updated in a while but it still works).