One of the very most important flaws in IB's line charts concerns the method used for summarizing data.
Medved's Quotetracker is superior in this very important respect. A QT line chart always includes the highest and lowest prices to have been received from IB's data feed, during any particular time interval on the line chart. IB charts, on the other hand, simply determine a set of equidistant points in time, {t1, t2, t3, ...tn}, and display the prices, {p1, p2, p3, ... pn}, occuring at each one of those equidistant points in time, while totally ignoring the highs and lows and all other price action occurring in between those points in time. The result is that as the time interval of an IB chart is increased, from seconds to minutes to hours to days, they become progressively less useful, because they contain progressively less information. Yes, the charts must summarize the data, but the problem is the particular algorithm used for doing so. QT's algorithm is vastly superior and more useful. IB should adopt the same method, so that IB's line charts will become far more useful.