This indicator by default comes with the MACD shown but can be switched to show the RSI instead. Settings for each indicator can also be customized as well as Buy/Sell signals given based on pull back crossovers that follow the 200 EMA of the price Chart. There's an above/below middle fill option you can use but I tend not to but I know some traders like to see when an oscillator is above/below the middle and use it as a trend diretion. By the way, the fourth setting for the MACD (which is 2 by default) is the size of the histogram.
Buy Signal = Price is above the 200 EMA. Current or previous MACD or RSI line is/was below middle line and now crossed above the signal line.
Sell Signal = Price is below the 200 EMA. Current or previous MACD or RSI line is/was above middle line and now crossed below the signal line.
There are alerts for each signal as well (MACD and RSI, both buy and sell).
Feel free to leave a comment regarding issues or suggestions for this indicator or ideas for the next one I should do :)