I guess it would have been a lot harder back in the day but today, making a chat application is pretty easy. You don’t have to spend much energy on it, all you have to do us use a clone script. You might find a few if you search for Whatsapp clone script or telegram clone script on google. These clone scripts are prebuilt applications that you can customize according to what you need. You don’t even have to do it yourself, the companies selling these clones will do it for you. Even if you want it for your business, this is the most feasible option. You can even integrate these systems into your already existing application without much trouble.
Just make sure you find a good clone from an experienced company with a good track record in this kind of a thing. The world of social media is evolving every day, if you have a killer idea with you, you can definitely give the competition a run for their money. Just look at how many applications have gone through our cellphones over the past 10 years. People might be a little reluctant to new things but if you give them something worth their while, they’ll definitely start using it. And who knows, maybe Facebook will like the idea and buy your company. If you’re into that kind of a thing that is. Hope this helps.