Chart Plotter apps for iPhone

I'm looking to install a chart plotter app on my iPhone and am wondering which one I should try. I am preparing for a 70 mile canoe race in Puget Sound and plan on using my iPhone as my primary navigation tool. I've always liked Navionics but it has some negative reviews, iNavX looks pretty good as well, and there are others. Please share your experience with any of them, I can use all the advice I can get.

Aqua Map seems pretty good.

Navionics has auto routing which is a nice tool,

I have used AquaMap on I phone and I pad for planning and navigatioon as a back up to my chart plotters. Here is a video on the use of Aquamap on an I pad.
The 70 miles in a Canoe Race in Puget Sound sounds like a lot of currents, so current and tide tables are essential! I would also want a hanld held Marine VHF, as well as read out on AIS signals, closest point of approach etc. Also wind predictions would be important. From the seventy48 web site, it appears as if most of the course can be on the Western side and not a lot of other boat traffic.

However there are certainly a lot of Hazards. Night, fog, rain all make it much more difficult. What type of craft are you in? A SUP vs a 10 man canoe are entirely different crafts, and offer different navigational and safety issues. Tell us about your crew and craft! (I love these water tribe type of events. This year is back to the Race To Alaska event a short time after this race. The best of luck!!

Thanks everyone!
Bob, my plan is to do the race in a 17.5' solo canoe that I am building out of cedar strips and fiberglass. It is nearly done. I will have a VHF and tide and current charts (well studied in advance) and the other safety devices. I have a fair amount of experience in canoes on rivers and bays but this will be a big challenge. I'll post a photo of the canoe when finished.