It would be helpful if, instead of just throwing out names, you also provided links. "Line" and "imo" are rather difficult to search for, and since you already

It would be helpful if, instead of just throwing out names, you also provided links. "Line" and "imo" are rather difficult to search for, and since you already know (of) them I'd assume you can provide links. It would also be helpful if you could provide brief reasons as to why one would choose one of those as opposed to, say, Signal or blabber/XMPP, for example. Thanks.