Dripcap

Popularly known as protocol and network analyzers or packet sniffers, these types of utilities are designed to intercept and log network traffic.
Created with the help of the popular Electron framework, Dripcap is one such utility that works just as well on all major operating systems out there.

Requires WinPcap in order to run

Launching the application is practically a walk in the park since it does not require any type of installation: just unzip the package and launch the app via its predefined executable file.
Although launching the app is incredibly easy, please note that this app requires a small set of relatively accessible requirements.
First off, you need to make sure that WinPcap is present on your computer. It is only after the famous tool for link-layer network access is installed that you will be able to properly launch the app.

Once you start the app, there's one more detail that needs taken care of

Upon first launching the app, you are greeted by a welcoming screen that allows you to quickly start new capturing sessions, to import PcaP files, visit the app's official Wikipedia page or access the Preferences section.
Head over to the Preferences section and install the utp Micro Transport Protocol decoder, within the 'Install' tab and that basically covers the requirements issue.

Well-organized main window and modern UI

From the application's main window, you can easily start analyzing network traffic by creating a new session.
This said, the app's main window is split into three parts. On the left side, the app displays a list of all captured IP addresses, while the right side is the place where you can get more detailed information about certain protocols such as Ethernet, IPv4, TCP and many others.

Both novices and advanced users will find this app quite approachable

Importing PcaP files can be easily accomplished from the File menu, new sessions can be started from the capture menu and accessing the Preferences section from the Edit menu.
It is also noteworthy that you can start or stop sessions either from the aforementioned Capture menu or from the app's minimalist top toolbar. Last but not least, you should also know that the utility provides you with a light set of UI Themes, available under the General tab, from the Preferences section.

Straightforward and user-friendly packet sniffer

To conclude, Dripcap is cross-platform and modern-looking packet analyzer or sniffer that comes with a well-organized workspace within which it accurately displays info about your network.
Lastly, we must point out that we would have liked this application way more if it would allow you to save and export logs.