iphone navionics app use in BWCA

[beer batter]

Have the navionics app loaded on my iphone, which has contour maps of lakes and uses GPS positional data to tell what depth you are at on the lake. Will I be able to use this in the Boundary Waters where there no cell towers? Not sure if the phone's use of GPS requires cell data.

[nofishfisherman]

The GPS will still work without cell coverage it may take longer to get your initial position without cell towers to assist but once its got your position it should work fine.

[beer batter]

thanks! I've done some unit tests by disabling both cellular and wifi, and it seems to work. Only concern would be the maps. Are they stored locally on the phone, or pulled in from the cloud? Again, they worked for me during my test, but I'm wondering if the maps are stored in flash right now because I had just used it.

Thanks again!

[nofishfisherman]

To get the detailed lake maps on the Navionics app you have to download the maps for a selected area to your phone so they should be there and accessible whether you have cell service or not.

You can tell if you have a certain area downloaded by zooming out on the map. Any area you have downloaded should be highlighted in bright yellow. The non downloaded area should show up as a dull brownish yellow color.

I have it on my android but I assume its the same for the iphone.

[beer batter]

right on! I see what you mean with yellow vs brown. Thanks again!

[Whoaru99]

FWIW, I just used the Android version on my Samsung tablet a couple weeks ago on Bowstring and Little Jessie lakes. My tablet doesn't have cell modem and of course there wasn't any WiFi out on the lake. Worked with the map segments I looked at in the cabin (and presumably downloaded there).

The only gripe I have is that at times the position/track update rate didn't seem very good at low trolling speeds. Not sure if that's an app deal or of the tablet GPS (1Hz). Seemed like at times there was quite a bit more than 1 second before it showed me moving on the map.

[bobbymalone]

The only gripe I have is that at times the position/track update rate didn't seem very good at low trolling speeds. Not sure if that's an app deal or of the tablet GPS (1Hz). Seemed like at times there was quite a bit more than 1 second before it showed me moving on the map.

I bet it's a hardware issue. I've had drastically different experiences with the same apps on different devices. My old phone lagged big time. My new phone, not so much.

There are some apps out there that can track your GPS refresh rate, if you are that interested. Never tried them though.

[Whoaru99]

Yup, after seeing the lag I installed one of those GPS tool apps. It showed 1Hz. Which, I understand 1Hz isn't fast by today's GPS standards, but the actual position update seemed much longer than that at times.

Not saying it couldn't be the tablet, but it doesn't seem to lag on other GPS apps like Google Maps. I just installed a Trimble GPS app, but haven't done much with it yet to see how that goes.

All in all I'm satisfied with the Navionics app and the maps seem accurate enough, just that occasional lag I noticed.

[marine_man]

When you're there, and confident you don't have any cell phone coverage, put your phone / tablet in airplane mode... you'll still have GPS service, but it won't drain the battery looking for service.

marine_man

[Wish-I-Were-Fishn]

When you're there, and confident you don't have any cell phone coverage, put your phone / tablet in airplane mode... you'll still have GPS service, but it won't drain the battery looking for service.

marine_man

Great idea