So you rate Signal then do you? When I heard about Encrochat being cracked I assumed that because it cost a grand it must be the dogs bollocks. But seemingly not...
Signal is the best encrypted chat app you can get. I'm not joking when I said the Snowden leaks showed even the NSA couldn't hack it. Signal has been upgraded a lot since then too, both technologically and financially - the protocol they used has been beefed up significantly and passed multiple independent audits, and the co-founder of WhatsApp quit after selling out to Facebook and invested $50 million to create the Signal Foundation.
Also there is safety in numbers when it comes to chat apps. The last thing you want is something that cost a grand and only criminals use. Internet traffic is all being monitored by intelligence agencies, so you want yours to blend in. The more people who use the same app as you, the better.
Encrochat was a super easy target because it had a small client base of around 1,000 and basically all of them were criminals. So if LE was watching your internet logs and saw connections to Encrochat they could be pretty sure you were a crook. They also knew only specific devices ran that software and could plan a malware attack easily, particularly when it was just regular Android with custom apps preinstalled.
A good few million people use Signal and most are not criminals, hence your traffic flows in a sea of millions of regular users and is a much more difficult target. LE would need to know a lot more than the chat app you use in order to target you. Knowing you use Signal would also not, in itself, tell them what phone you use, what OS it's running, and what vulns they may be able to use to attack it. Whereas this was exactly the case with Encro.
But yeah Signal itself is as solid as it gets mate.
Money does not equal quality when it comes to cryptography and cybersecurity in general. Much of the most secure software in the world, trusted by huge companies everywhere, is open source.