macOS Catalina aka 10.15, the newest version of macOS launched by Apple has finally been launched. The new update has brought in a ton of features that are helpful for all Apple device users.
This new OS, Catalina has done away with the iTunes Application. The application that has been a staple since 2001 has now been split into three applications i.e Music, Podcast and the TV application which will be launching this fall.
macOS Catalina Launched!

The new update will not have any support 32-bit apps in macOS Catalina, and you’ll get a warning when you install the update. It can only support 64-bit apps, and that means that some of your older apps that haven’t been updated for a while won’t run at all. The Dashboard feature, which has long been disabled by default, has been officially removed in Catalina.
The update can be done by checking the Software Updates section in System preferences. The MacBook devices that have support for the Mojave OS can run macOS Catalina.
REMOVAL OF iTunes:

iTunes finally gets the boot from Apple after existing in its devices for 18 years. iTunes has now been broken down into several applications i.e Apple Music, Apple TV, and the Apple Podcast. Apple music does retain the same logo as the iTunes Application. All your songs, podcasts will be kept in sync with the help of iCloud.
ADDITION OF SIDECAR:
Sidecar is a new application that has been designed to use an iPad as a secondary display with your Mac. It can be accessed in the Airplay interface.
The Supported Devices are:

Sidecar lets you either mirror your display or extend it to the iPad and because the Apple Pencil works in Sidecar mode, you can use the Apple Pencil as a mouse or as a drawing implement in apps like Photoshop.
FIND MY INTRODUCED!

Find My is a new application that combines the Find My Mac feature previously available via iCloud and the Find My Friends apps from iOS devices into one app that’s available on iOS and, for the first time, Mac. It works even when the device is not connected to Wifi or Cellular connection.
The feature works by utilizing crowd-sourced location information delivered through Bluetooth signals. Basically, your devices give off a Bluetooth signal that can be picked up by other nearby iPhones, iPads, and Macs, relaying that signal back to you so you can find your missing device.
Catalina includes an activation lock, which you can use to Erase or lockdown your Macbook if you lose it. Apple Watch can be used to authenticate your Macbook using the new T2 chip. The enhanced Gatekeeper will check for any malware and flaws in the applications.
All Other Updates:

Photos Application has got a refresh by adding a new tab, A new ScreenTime Application has been added to monitor usage times and Parental Controls, Notes Application has been updated to have a new gallery view and Reminders has been given a facelift.

Safari has received a performance update to access the start page and warn about weak passwords, Now Mail has features to easily block senders, Quick Time Player Supports PiP (Picture in Picture) mode for easy playback, iCloud can now be used to generate a private link to share folders and iCloud details can be accessed through System Preferences.

Apple has finally added Apple Arcade for macOS Catalina so users can use it to play on their Macbooks!.
The annual update issued by Apple this year has been one of the best released to date. The update has been filled with getting rid of the old and introducing new features, which is a great move that Apple has pulled. We wish we keep on getting such good updates.