There was a time when GPS signals were basically scrambled a bit to reduce their accuracy. If you had the right codes you could 'unscramble them' and get back to the original accuracy. That was undone in the year 2000. See Military Unscrambles GPS Signals | Science | AAAS ).

There was a (relatively recently) time when civilian GPS used a single GPS signal, while the military used two. That might have changed - don't know.

dave

I just downloaded Strava. I haven't poked around too much with it, but it looks like I have to tell it that I'm about to ride my bike and tell it that I'm done. Is that correct?

The old app, LG Health, the 8 miles in 40 minutes got me curious and I checked the log. It appears to be getting my average speed right, but it's wildly inaccurate about the length of time I'm on my bike. That part seems to be why it's not recording my miles right.

Tap the horizontal bars beside Feed. Select record activity. Select Start. It will auto pause until you start riding. When you are done press finish. Then save.

If apps are draining your battery quickly try a combination case/battery like the Mophie Juice Pack, LifeProof or similar battery-charger-case doodad.

My iPhone 4s wouldn't quite last a full day running activity apps and the occasional photo or peek at a map. So I got an new/old stock Mophie Juice Pack Air, the smallest and lightest battery case Mophie made for the 4s. It extends the run time just enough to make it through 12 hours or longer if I don't turn the display on too often for photos or maps. Cost only $3 through Amazon Warehouse because it was in a shop worn carton but works fine. I'd definitely consider a newer full size Juice Pack for a newer phone, although Mophie makes them only for the iPhone and a few high end Android phones.

It was more cost effective just to buy a new Moto e4 on a Verizon prepaid account than spend too much more for a battery/case for the old iPhone.

If the LG Health app features auto-pause/resume it may not suit your riding speed and style. Strava is pretty accurate about recording only moving time.

My battery isn't the greatest, but my normal usage leaves me with 25-30% at the end of the night.

LG Health just auto runs all the time. I didn't even know I had it until about 4 months after getting the phone when I was searching the full list of apps for something, and it had all four months of activity data recorded and stored. It's kinda weird though when it comes to riding my bike, if I mount it on my bike it doesn't record any cycling activity, but when stashed in my backpack it does register me as cycling.

Battery life for a bike phone uses as GPS is a problem. If you want to use your primary phone as your trip tracker, fine. As long as it's in your pocket running it's GPS app with the screen off it should be fine for hours.

If you want to have the phone mounted on the handlebars so you can see it, the solution is to have a second phone to use as a dedicated bike computer.

Older used Android phones are CHEAP. And plentiful.

Find one with a good sized battery, half decent screen, and a working GPS and you're set.

The screen on any phone takes up the vast majority of battery use. Nothing you can do about that as you need it on and at full brightness.

But other battery hogs are things like the cell radio. If you have a dedicated bike phone that doesn't need an active internet connection (load the maps at home on Wifi) you can put the phone in airplane mode and it's a huge battery saver. GPS is a passive listening antenna, not a broadcast antenna. It works fine in airplane mode.

Samsung makes an 'active' version of the Galaxy S series phones that are great for this because they are fully waterproof and more resistant to bumps and drops. Perfect for something that might get caught in the rain or knocked off the handlebars. You can get a 3 year old one affordably. If you're not really worried about waterproofing, you have so many good options for a cheap used Android phone it's insane.

You can also improve battery life on a bike phone by having the screen go off after 15 seconds. The catch on this is that you need to have a phone with a tap to wake feature where you can tap the screen and have it come on. When you're riding, tapping the screen isn't a big deal. Finding the power button on the side can be a hassle.

You can also strip the phone down to it's core needs. You can disable of freeze all kinds of stuff like most of the google apps that run in the background. You can get rid of the battery guzzeling Facebook app. Disable settings like syncing and calendars and all sots of stuff like that you will never need on a bike phone. Makes the phoen run really streamlined and efficiently.

I leave my screen on. But in airplane mode just running GPS with a 3500 mAh battery with most of the apps needed to make a phone as phone disabled. I can get a 4 hour ride in no problem. If I didn't keep the screen on I'm sure I could get 7-8 hours out of it.

I did a thorough testing of the cycling apps available on Google Play Store. I compared each one against my cyclocomputer for accuracy, and used them in the same "circuit" around my home, which included fast descents, wide avenues, narrow urban streets lined with tall buildings, crowded and abandoned roads.

I'm going to make a post about it and link to this one once I have it written. Stay tuned!

Hey there! I have posted my impressions of a bunch of cycling apps rights here:

My test of Android-based Cycling Apps

I did the tests for myself, but after reading this thread I realized someone else might want to know about it. Since the OP wants to take both riding and walking into account, I can recomment the UrbanBiker app, which is a true multi-modal app.

Read my review and comment if you can.