What is it you're looking for actually? "Best" is subjective to the person's needs.
For example for me, the best is signal but I would much rather use something decentralised that still allows friends and family to find me easily using my phone number. Stories / client defined groups without notifications are also very useful to me. Also a native desktop app (aka not a locked down browser running some local webpage) would be awesome. But such an app doesn't exist yet.
What would you need and prefer?