With Pattern Keeper you can view and annotate PDF cross stitch charts. There is an initial free trial period then there is a one time charge to continue to use the app.
The app is still in beta and works great with some charts but will not work at all with other. In general the app works best with full coverage pieces and backstitches are not supported. Also note that scans do not work. It has to be an original PDF pattern.
The app is tested with charts from Paine Free Crafts, Tilton Crafts, Haed, Artecy, Charting Creations and The Cross Stitch Studio. However there is no guarantee that all charts from these vendors will work. I'm NOT affiliated with any of the listed designers and all questions about compatibility should be posed to me not the designers.
View chart as one continuous pattern. Easily stitch over page breaks
Highlight symbols to see where to stitch. When highlighting the thread number of the symbol is shown. No need to flip back and forth between the chart and the legend.
Mark finished stitches. Select easily by swiping horizontally, vertically or even on the diagonal. It is also possible to mark an entire 10 by 10 square. If you import a chart that already have annotations in it we try to import that as your current progress. Finished stitches are displayed in color making it easy to navigate and compare with your stitching.
Mark where you parked your threads and in what corner of the square they are parked.
Keep motivated by tracking of your progress. Get a tally of how many stitches you finished today and in total and see how many stitches are left of each thread.