If you ask me I would like to suggest you that never depend on the signal indicator in crypto trading because many indicators can give the wrong signal sometimes. use a combination of indicators and go ahead. i have seen many indicators giving false signals and which leads traders to the loss.
One indicator which is Known as RSI (Relative Strength Index) that gives us the signal to buy and when to sell if it is below 30 so it means it is a good opportunity to buy and if it is above 70 it means it is not good time of buying. DYOR
I agree with you that signal opportunities should never be used in crypto trading.I have seen that there are many Telegram groups from where crypto trading signal indicators are provided. We should give priority to our own efforts in trading. I used to use signal indicator from telegram group once while trading binary.But in the beginning I got very good singles and several times my friend and I got good profits.But due to one wrong signal one day we lost all our gains since then we stopped taking telegram group signals and still trade according to our own efforts.