mPilot has been consistently evolving (for us) and is now a half-decent product. On an iPad Pro it’s responsive and you can dig down and/or search to find lots of useful information. The annotation tools are a bit of a regression in the latest version, though. Company layers, EROPS circles, that kind of thing are done pretty well and it feels more like an actual electronic charting application than a library of paper charts copied onto a screen.
One thing that is utter garbage is the documentation section. You have to know exact details of what you want and exactly where it is before you can find it, which kind of defeats the object - it feels actively user-hostile in this respect, to the point that we publish this section as a pdf and use another app to search it.