I Use My Self-Heating Coffee Mug Every Day, and All of These Options Are on Sale Right Now

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When the Ember mug first hit stores in 2016, I was skeptical of its high, triple-digit price tag. Surely a coffee mug with a built-in heating element can’t be much better than a thermos, right? But now that I have one, I can’t go back. If you’re like me and drink coffee every day, you have to get a self-heating coffee mug before Prime Day ends—and competitors’ sales at Walmart, Best Buy, and other stores start rolling out.
Since its introduction, Ember has had a few competitors in the marketplace, but in my opinion, the original model is still the best. This coffee mug, sold at Walmart, comes in two sizes: 10 ounces (285 ml) and 14 ounces (455 ml). Both are currently priced about the same and come with a charging pad. (It will get hot without the pad, though, if it’s charged.)
As someone who loves sipping coffee or hot chocolate for hours, but has burned myself more often than I’d like using a thermos, I think this device has completely changed the way I drink coffee. It’s never too hot or too cold, which is especially handy for drinks that cool down quickly, like hot chocolate. The downside is that you have to use the companion app to set the temperature you want, but for degree-precise control, that’s a hassle I’m willing to live with. Plus, it notifies me when my drink is at the right temperature, which is handy.
Sure, it’s not exactly travel-friendly, but while Ember makes a thermos that uses the same technology as the mug, it’s not currently on sale. It’s also worth noting that, depending on how big you like your cups, 14 ounces might not be enough for you.
Alternatives to Ember Mugs
Even with my readings, I understand that the Ember mug may be too complicated or too expensive for you. In that case, try one of these options.
Nextmug is perhaps Ember’s main competitor, offering similar features but without an app. Like Ember, it’s a battery-powered mug with a charging stand. Instead of an app, you use a button on the mug to select one of three temperature settings: warm (130 degrees), hot (140 degrees), or steaming hot (150 degrees). There’s no temperature control, but if any of those settings work for you, you might like this mug better than Ember.
Or, for a little extra, you can go for the Nextmug Plus , the largest option on this list, with a 450ml capacity. It’s a great option if you like big cups. Plus, both versions of the Nextmug come with an extra charging stand and a travel lid (it doesn’t close completely, but it’s better than nothing). Like the Ember, Nextmug makes thermoses, but they’re also currently out of stock.
Finally, there’s the Kepwam mug if you’re looking for a budget option. Both the Ember and Nextmug are priced about the same right now, but this one is about half the price. On paper, it’s similar to the Nextmug, with three temperature presets and no app. Those presets are a little unusual for my tastes — 113 degrees, 131 degrees, and 149 degrees — but you might like it if the Nextmug doesn’t have them. It’s also 16 ounces, making it larger than the Ember mug or the basic Nextmug, though it doesn’t come with a second charging pad. On the plus side, it includes a removable, snap-on lid that closes completely. It’s not a big-name product, if you couldn’t tell by the weird variation on “keep warm” it’s named after, though Amazon reviews consistently give it four to five stars.
Looking for something different? Retailers like Walmart, Best Buy, and Home Depot are running Prime Day sales that are especially helpful if you don’t have an Amazon Prime subscription.
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Walmart’s Prime Day sale runs through Sunday, July 13, and includes discounts of up to 50% . It’s an especially great deal for those with a Walmart+ membership.
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Best Buy’s Prime Day sale , Black Friday in July, runs through Sunday, July 13, and is one of the best tech deals online . It’s an especially good deal for My Best Buy Plus or Total members.