LINE 4+

I haven't had any of the problems with video calls that some reviewers are reporting. Even group calls work fine for me.
Contrary to, say, Skype, LINE properly syncs chats across devices, so I have no problem regarding this either.
I don't use voice for anything on any of my devices, and definitely not on my computer, so limitations of this interface don't affect me directly, but I have noticed that some of my interlocutors sometimes with strange chat lines that they couldn't possibly have typed.
I saw one review lamenting the lack of spell checking on this mac OS version. Well, at least, unlike the iOS version, the macOs version won't try to sanitize my chats :-)
I took one star off because the UI is somewhat dated and because the sticker suggestions sometimes take a loooong time to pop up, and sometimes don't show up at all.

It’s a good messaging app. Having it on the desktop is one of many reasons why I use Line. This means I can easily switch from my mobile to my computer. However, to say it is such an elegant or wonderful or magnificient app, is a way too much in my opinion. Objectively, there are some features that it needs to improve to come to that rate. There are clearly gaps between the mobile apps and the desktop one: Something so simple as message has been read, theme, sticker shop, etc. The improvement like the options to show timeline or not can be useful to some users, but I definitely expect something more than that in the update. And honestly I don’t like the current size of the app; we can’t resize the width of the main window while I don’t see the reason why I want a window that big for my Line app on my screen. I hope to see more improvements in the future. Until then, I’ll stick with 3 stars for now; it’s good, but improvements are needed. If you do care for the improvement of the app, rate objectively and do not simply compliment cheaply.

I have been using LINE on the iPhone for 10 months and my Mac Airbook for 9 months. Love the LINE iOS app but the desktop version is flawed. My biggest gripes are:
Keyboard Shortcuts either work very slowly or don’t work at all: I use the keyboard shortcuts feature in Apple iOS and Mac OS to save keystrokes when typing IM messages. Works great in LINE iOS but is flawed in the desktop version. When I type in a shortcut abbreviation, it is substituted immediately on LINE iOS (e.g. “ilu" turns into "I love you”) but on the desktop, you might have to wait 3-4 seconds, and half the time it doesn’t work all. This is a problem with LINE desktop as shortcuts work just fine in other apps on my Airbook.
Cannot Delete or Hide Contacts: You cannot delete a contact in LINE, either in the iOS app or the desktop app, but at least in the iOS app you can “hide” contacts. Not so in the desktop. It doesn’t even recognize that you have hidden the contact in the iOS app. Who wants to be constantly confronted with a list of their old girlfriend/boyfriends everytime they use LINE?
Take/Send Photo: Cannot take photo or send photo from “Pictures” within the LINE app on desktop. You can send files from within LINE, but you cannot take and send a photo directly, nor can you directly access and send photos from iPhoto library or photostream. So why not?

I keep waiting for some of these issues to be addressed but in 9 months, nothing.