Reddit reviews Newmowa AZ16-1 Replacement Battery (2-Pack) and 3-Channel USB Charger for Xiaomi YI AZ16-1,AZ16-2 and Xiaomi Yi 4K,Yi 4K+,Yi Lite,YI 360 VR Action Camera(Not for Discovery Version)
We found 3 Reddit comments about Newmowa AZ16-1 Replacement Battery (2-Pack) and 3-Channel USB Charger for Xiaomi YI AZ16-1,AZ16-2 and Xiaomi Yi 4K,Yi 4K+,Yi Lite,YI 360 VR Action Camera(Not for Discovery Version). Here are the top ones, ranked by their Reddit score.
More Power for More Video: Each1400mAh battery offers you more power to shoot more videos; charge inside the camera or with 2.1A input charger to maximize charging efficiency3 Ways to Charge: Can be charged by wall, car, and power bank charging for added convenience.Fully Compatibility: Made to the exact specification of YI AZ16-1 battery, compatible with YI 4K/4K+ action cameraCharge 3 Batteries at the Same Time: Innovative design allowing for charging 3 or 2 batteries at the same time and 3 independent Smart LED light indicated RED when charging and GREEN when complete100% Safety Guarantee: Features four layers of protection (over-charging, short-circuit, high-temperature, and surge protection) with a high-quality, fire-resistant construction
I've got a Contour Roam as well, which I like as a helmet cam because I'm a terrible, vain creature and think conventional action cams stuck to the top of helmets look awfully silly.
If you're less vain -- or if you can find a Contour Roam at a reasonable price point, or you want better video quality more than you want to look cool -- I'd also recommend a Yi 4K (presently $170 on Amazon, but you'll probably want a ~$15 - $40 waterproof housing, and also some way to mount it). I've got one that I've mounted under my handlebars (in addition to wearing the Contour on my helmet) and I'm very impressed by it. It's got a removable battery, too, and you can get extra batteries real cheap.
One final option, if you're inclined to the action cam form factor but don't want to shell out $170 for a Yi 4k (or even more for a GoPro or what-have-you) is the recently-announced and very well-reviewed Yi Discovery, which as far as I can tell (though I don't own one, so no guarantees) is more-or-less the same thing as the Yi 4k, sans the mostly-useless image stabilization feature and with slightly slower frame rates (4k @ 20fps, 1080p60), but it's only $60, which is a steal. It uses the same batteries and other accessories as Yi 4k.
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Also: r/bikecammers is a good place to ask for advice on this stuff.
I put a lot of research into my recent GoPro purchase. I actually ended up going with a different camera, the YI Action camera. Its a better camera for a better price.
https://www.amazon.com/YI-Action-Sports-Camera-Control/dp/B01FU9ZIMU#nav-search-keywords
Extra batteries and a charger are a must in my opinion.
https://www.amazon.com/gp/aw/d/B01HM8L0Z6/ref=mp_s_a_1_7?ie=UTF8&qid=1518590419&sr=8-7&pi=AC_SX236_SY340_FMwebp_QL65&keywords=yi+action+camera+accessories&dpPl=1&dpID=51CLAbP-ksL&ref=plSrch
GoPro accessories fit it as well.
https://www.amazon.com/gp/aw/d/B00XHSKKXE/ref=mp_s_a_1_3?ie=UTF8&qid=1518590526&sr=8-3&pi=AC_SX236_SY340_FMwebp_QL65&keywords=gopro+accessories+kit&dpPl=1&dpID=61v4Wvt6YjL&ref=plSrch
I bought everything above and love it. Good luck to you in your purchase and even more luck with fatherhood!
This is what I got. They work great! https://www.amazon.com/gp/aw/d/B01HM8L0Z6/ref=yo_ii_img?ie=UTF8&psc=1