Here, we have a look at the yearly (365 day) and quarterly (91 day) SMAs, which are black and red, respectively.
Two bullish signals to note:
1.) We see a daily close above the yearly MA, which has, so far, been a fairly reliable indicator of when the next bull market might be starting. We see a series of about four consecutive closes above that line between July 27 and 30th of last year (2018) that marked a failed breakout after the bearish cross (of the quarterly under the yearly) had occurred, so it certainly isn't a 100% reliable indicator. That said, the more closes we get above this line, the more confident we can be that this is a confirmed bullish signal. So far, we're waiting on day two's close...
2.) We see price trading near the upper 50% envelope of the quarterly MA; historically, a positive indicator that the market has turned bullish. You can look at the blue arrows marking both today's price, which is nearly touching it, and the last time that it had occurred after a bear market, in late 2015.
This is not to say that I'd recommend longing BTC from its current price, rather that I expect the next correction will be just that, a correction within a bull market. I'm calling that the low is in, but I wouldn't be surprised if price drops back down to the ascending triangle breakout area (around $4,100) and even a bit lower.
That said, historically, in bull markets, buying when the price dips below the quarterly moving average has been a "strong buy" opportunity and I'll be watching very closely for these moments in the future, up until it is invalidated by either price moving near the lower envelope or another bearish cross (and, yes, I realize that the bullish cross has yet to happen, which, technically, means that the bullishness has not yet been confirmed according to this MA system).