My Garmin 64 GPS uses two AA batteries, disposable or NiMH. It can also run on a proprietary Garmin battery pack. And if you use that Garmin battery pack (that consists of two AA NiMH batteries), you can charge the battery pack with a USB cable (mini, not micro USB). Or, you could do what I did, use a small piece of metal held in with tape, the two NiMH batteries I put in push on that metal piece which pushes down on a button to fool the GPS into thinking that the proprietary battery pack is installed. I use that GPS for bike touring, when I am down to one bar on the battery scale, I plug it into my pass through cache battery pack that is charged by the dynohub for maybe an hour and then unplug it. But, the way I do that if you wanted to use disposables, you would have to remove that little piece of tape holding that metal on the button.

Most months my cell phone is not used, I only have it for travel. I give out my cell number to almost nobody, I do not want them to call or text me, and then they get pissed when I do not respond. If you give people your number, they assume that they can call you and actually get you. I only give out my land line number.

But I carry the phone on the bike on longer rides in case for some reason I need help. When I travel, I usually am trying to get a forecast a couple times a day so I can plan what I want to do and when. And if I am on a bike tour, backpacking or canoe trip my sister will panic if she does not hear from me every 2 or 3 days, so I need to make some calls or send some e-mails when I travel so the family does not worry. That said, the phone is always either off or in airplane mode if I am not using it.