My GPS is nearing end of life. I was thinking of using my iPhone instead of buying a dedicated GPS but there are so many different apps I don't know where to start. (And trying out different apps doesn't interest me much) I'd like to be able to load topo and sat maps for hunting areas. I'm sure some have set up an iPhone for this.

What's the best setups, drawbacks you have noticed, etc?

I don't keep a GPS turned on much as I use paper maps mostly with GPS for waypoint marking and orientation. Still, what do you do to get decent battery life with an iPhone being used as a GPS?

I volunteer with a search team. Quite often we are called in to search for folks believed to be dead crime or suicide victims. We use both, but find that a dedicated GPS is much better. Some of the apps for our phones are useful, if they work. Sometimes they don't. A cellphone app saved myself and others from having to backtrack about 5 miles during a search in April. Two weeks ago during another search I found the same app almost useless in another area about 400 miles away.


The accuracy is poor as well. Often we will find an article of clothing, a cell phone, some bones etc. We mark the sight with flagging tape, record the GPS position and call it in for detectives to investigate further. I've seen phones off by 400' on the actual location.

Battery life is roughly the same, although a lot depends on the individual device. But I can always carry spare batteries for the GPS. Not so with most phones.

Sounds like a wrong datum setting, IE NAD 27 vs WGS 84

I use Backcountry navigator pro for $10 instead of a gps. You can get free USGS topos and sat maps. You can also get Noaa charts. I use a Galaxy Note, but I've seen others in my group use this with iphones. I know my phone uses both the us and russian gps systems. Accuracy is excellent. I'm not as sure with the iphone, but have heard no complaints. Battery life is decent, but just don't keep it on all the time. I also use my phone as a Kindle, so I don't have to take a book. I make up for it with batteries which are weight neutral, but have a volume advantage. It is not waterproof nor as rugged as a GPS, but I keep it in a ziploc and take care of it like I would a nice piece of glass.

For batteries, I use an external battery from Anker.

In summary, this is a cheap system to experiment with. I think it's worth $10 to try and if you like it, you can buy a $30 external battery for longer use.

I use Gaia. You can download numerous maps including aerial photos before getting to the backcountry. I have tried many GPS Apps and this one is my favorite. It has proven to be reliable and user friendly. There may be better apps out there but this is really good. I think it is a $10 app and the maps are free.

Gaia x 2

I use the "Topo Maps" app on the iphone. It uses topo maps that are downloaded to the phone beforehand and therefor does not need cell service or wifi.

For absolute maximum battery time, don't run GPS apps with map display. I use the "Tomtrails" app that only dumps coordinates. I like the convenience of the UTM coord dump and use that with a real map that also has a UTM grid. I tend to print out custom hi-res maps of where I am going with UTM grid overlays and laminate the paper in plastic to weatherproof them. I can then just write on the plastic with a Sharpie - use diff colors even

Thanks for the inputs so far. Keep them coming. From what I've read looking at the Gaia site, I think Topo Maps is related to Gaia. I'll give Gaia a shot.

Alukban, explain what Tomtrails does again? Does it just give the coordinates on demand in plain lat/long or UTM or what? How do you set up your phone for best battery life while using Tomtrails? How long does it take to get a fix when you turn the phone back on? Thanks in advance for any details.

It's hard to improve on the dedicated Garmin handheld GPS models but I already have the iPhone and will be carrying it anyway. And I would prefer something where downloading maps isn't such a pain in the butt and/or expensive.

I use Phil Endecott "Topo Maps". You download whatever USGS quads you want. It is identical to the USGS quad maps, showing trails etc. At least, every place I have a (paper) map of, appears exactly the same on my iPhone topo.

Tracking with the GPS will eat up your battery power in a hurry, regardless what type GPS, hiking, topo, golf GPS, the map function on your phone, doesn't matter, It's been my experience that using a GPS will use up the battery quick.

Here's what I do. I rarely go into an area that I do not have a map. When backpack hunting out west, I use a map and compass. I will turn on the phone just to confirm my location, then turn it off. This allows me to keep my iPhone power for several days. It's lasted for a four day hunt with power to spare by doing this. But I want to know where I am on a map and not totally depend on an electronic device.

I also carry a Mophie power pack for recharging though as yet, have never needed it.

If I'm on a day hike or hunt, I can pull up the map and only occasionally turn on the GPS to pinpoint my location on the map then turn off the GPS locator while still keeping the map up.

It's the actual GPS tracking that uses so much battery power.

I have the newest iphone and an older Garmin etrex Hcx, the iphone is no match for topo maps and waypoint tasks.