I've been working on a free windows portfolio app (http://salerth.github.io/CryptoPath/) and next I wanted to add better charting.  Either just rendering MACD charts, or doing the calculations and showing which markets are in buy/sell phases.

Are there any APIs (prefer not to do screen scraping as it's not as reliable) for getting longer term price histories for different altcoin markets?  The ones I can find seem to be 24hour averages/highs/lows only... am sure I'm missing one!

Thanks