Originally announced by third-party developers Lane Musgrave and John Arrow back in early March, one of the biggest concerns of the battery-boosting accessory "Reserve Strap" was its use of the Apple Watch's heart rate sensor as a way to provide power to the wearable. Although it was unconfirmed, there was always a possibility of the Reserve Strap obstructing normal functions of the heart rate sensor, or causing the Watch to not function altogether by interfering with skin contact completely.

Last week, after getting their hands on an Apple Watch, Musgrave and Arrow have gone back to the drawing board on the design of the Reserve Strap, coming up with a new look that acts as more of a traditional Apple-made band without blocking the heart rate sensor at all. The new Reserve Strap aims to use the 6-pin diagnostic port - hidden inside of the band port on the bottom of the Watch - as the main source of providing power to the device, shirking the heart rate sensor's magnetic inductive charging altogether.

reserve strap change

The Original Reserve Strap design (left) vs the new design (right)

Finally getting our hands on the Apple Watch has further confirmed the immense value of the Reserve Strap. Since release day, we've been executing series of tests on the Apple Watch and have some really exciting news to share today.

We've developed and tested a completely rethought design that takes advantage of the 6-pin port underneath the band slide of the Apple Watch. This port hadn't been deciphered by anyone until now but we've been able to make significant enough observations so far to warrant shifting our development focus to this new method. We're looking forward to sharing more design details and technical specification of this new Reserve Strap as soon as we can.

The company claims in its blog posts that its engineers have "been able to independently confirm that the 6-pin diagnostic port underneath the Apple Watch case can be used for charging." They continue by also noting the diagnostic port will allow for not only a higher charge capacity, but faster, more efficient charging times. The blog post also notes that the new method should improve durability of the strap as a whole and eliminate "any interference with Apple Watch functionality including taptic feedback and heartrate sensors."

reserve strap port sketch

Initial renderings of the new design (left) vs fully realized 3D model (right)

No word was given on the planned Kickstarter for the Reserve Strap, but those interested can still pre-order the device from the company's official website for $249.99. Color options will include white, gray and black, and customers will be able to choose between 38mm and 42mm strap sizes to fit their preferred Apple Watch size.

Related Roundup: Apple Watch Series 9
Buyer's Guide: Apple Watch (Neutral)

Top Rated Comments

DannyT2011 Avatar
116 months ago
It won't work. Look at the connector. Those of us who have our watches already know that the way to attach a strap is to slide it in. Straps won't slide with a big connector sticking out of them.

It looks like there are buttons on either side of the strap that you would pinch to insert/release. Perhaps as you pinch them, the connector will retract and then will connect to the port when you release them?
Score: 13 Votes (Like | Disagree)
elmateo487 Avatar
116 months ago
It won't work. Look at the connector. Those of us who have our watches already know that the way to attach a strap is to slide it in. Straps won't slide with a big connector sticking out of them.

Lol. This made me laugh. They have engineers who can extract info from a diagnostic post... Yet you think they didn't think of that? Especially since they have one in their hands now.
Score: 6 Votes (Like | Disagree)
Jandmtv Avatar
116 months ago
Apple covered that port for a reason. Good luck with that strap in the rain.

Yup, only to include it as a new feature with the watch2.
Score: 6 Votes (Like | Disagree)
shareef777 Avatar
116 months ago
Apple covered that port for a reason. Good luck with that strap in the rain.
Score: 6 Votes (Like | Disagree)
dannys1 Avatar
116 months ago
I take it these people are aware that having batteries in a watch band is something Apple has patented.

Which begs the question, why didn't they launch with battery bands?
Score: 6 Votes (Like | Disagree)
shareef777 Avatar
116 months ago
We all know the watch needs the iPhone to operate, and the iPhone doesn't last more then 18 hours so why does the watch need to? If you have to recharge your iPhone every night, it should be easy enough to charge the watch as well.
Score: 5 Votes (Like | Disagree)

Popular Stories

reset password request iphone

Warning: Apple Users Targeted in Phishing Attack Involving Rapid Password Reset Requests

Tuesday March 26, 2024 4:34 pm PDT by
Phishing attacks taking advantage of Apple's password reset feature have become increasingly common, according to a report from KrebsOnSecurity. Multiple Apple users have been targeted in an attack that bombards them with an endless stream of notifications or multi-factor authentication (MFA) messages in an attempt to cause panic so they'll respond favorably to social engineering. An...
maxresdefault

Apple to Launch New iPad Pro and iPad Air Models in May

Thursday March 28, 2024 11:07 am PDT by
Apple will introduce new iPad Pro and iPad Air models in early May, according to Bloomberg's Mark Gurman. Gurman previously suggested the new iPads would come out in March, and then April, but the timeline has been pushed back once again. Subscribe to the MacRumors YouTube channel for more videos. Apple is working on updates to both the iPad Pro and iPad Air models. The iPad Pro models will...
Generic iOS 18 Feature Purple

iOS 18: What to Expect From 'Biggest' Update in iPhone's History

Wednesday March 27, 2024 11:10 am PDT by
At least some Apple software engineers continue to believe that iOS 18 will be the "biggest" update in the iPhone's history, according to Bloomberg's Mark Gurman. Below, we recap rumored features and changes for the iPhone. "The iOS 18 update is expected to be the most ambitious overhaul of the iPhone's software in its history, according to people working on the upgrade," wrote Gurman, in a r...
maxresdefault

Apple Announces WWDC 2024 Event for June 10 to 14

Tuesday March 26, 2024 10:02 am PDT by
Apple today announced that its 35th annual Worldwide Developers Conference is set to take place from Monday, June 10 to Friday, June 14. As with WWDC events since 2020, WWDC 2024 will be an online event that is open to all developers at no cost. Subscribe to the MacRumors YouTube channel for more videos. WWDC 2024 will include online sessions and labs so that developers can learn about new...
apple maps 3d feature

Apple Maps May Gain Custom Routes With iOS 18

Tuesday March 26, 2024 3:10 pm PDT by
Apple may be planning to add support for "custom routes" in Apple Maps in iOS 18, according to code reviewed by MacRumors. Apple Maps does not currently offer a way to input self-selected routes, with Maps users limited to Apple's pre-selected options, but that may change in iOS 18. Apple has pushed an iOS 18 file to its maps backend labeled "CustomRouteCreation." While not much is revealed...
General iOS 17 Feature Orange Purple

Apple Releases Revised Versions of iOS 17.4.1 and iPadOS 17.4.1 With Updated Build Number

Wednesday March 27, 2024 5:59 am PDT by
Apple on late Tuesday released revised versions of iOS 17.4.1 and iPadOS 17.4.1 with an updated build number of 21E237, according to MacRumors contributor Aaron Perris. The updates previously had a build number of 21E236. The revised updates are available for all iPhone and iPad models that are compatible with iOS 17 and iPadOS 17, but they can only be installed via the Finder app on macOS...
applephilschiller

Apple's Phil Schiller Works 80 Hours a Week Overseeing App Store

Wednesday March 27, 2024 2:03 pm PDT by
With the App Store and app ecosystem undergoing major changes in the European Union, The Wall Street Journal today shared a profile on App Store chief Phil Schiller, who is responsible for the App Store. Though Schiller transitioned from marketing chief to "Apple Fellow" in 2020 to take a step back from Apple and spend more time on personal projects and friends, he is reportedly working...