What is the Best Smart Mug? (Tests, Differences, and Rankings)

What is the Best Smart Mug?

(10 minute read)

What is the Best Self-Heating Mug?

This is your guide to find the best self-heating mug for yourself or to give as a gift.  You'll see three popular mugs representing three price tiers, including Kepwam, Nextmug, and Ember.  We'll start with some tests, then we'll look at similarities and differences, and last we'll recommend which mug is best for different uses and situations.  Let's find your perfect self-heating mug!

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What's Next?

• Video review
• Big Picture
• Recommendations
• Testing
  • Heat up and maintaining temp tests (battery life)
  • Recharge test
  • Scratch test
  • Waterproof test
  • Customer service test

Amazon Disclaimer
If you find this information helpful, I hope you'll consider using a link to buy.  We're part of the Amazon Associates program, and if you click a link then purchase, we earn a small commission at no extra cost to you.  It's the main way we can continue to provide detailed, unbiased reviews without relying on direct sponsorships.  Thank you!

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​Video Review: What is the Best Smart Mug?

If videos are more your thing, check out our Youtube video that covers most of the same information.

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The Big Picture

We tested and compared these three top-selling options on the Amazon US marketplace.

Kepwam (Budget)

Retail Price: $69.99
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​Best For:

• ​Battery life
• Lightweight
• Simplicity
• Bigger handle
• Travel

See Kepwam

Nextmug (Mid-Tier)

Retail Price: $129.95
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​Best For:

• All-around and gifting​
• Comfortable handle
• Smallest charging coaster​
• Easier to use than Ember, and more info than Kepwam

See Nextmug

Ember (Premium)

Retail Price: $149.95

Best For:

• Heat rate
• Recharge rate
• Level of control (app needed)
• Information (app needed)
• Name recognition

See Ember

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Recommendations for the Best Smart Mug

Our Recommendation:
Nextmug is an excellent choice as a gift for a mid-range option for yourself.

It has a heftier, more premium feel and look than Kepwam and the charging coaster is smaller and sleeker, so it will have a bigger impact as a gift.  The curved inside profile of the handle also feels much better compared to the more angular handle you get with Kepwam.

On the other end of the spectrum, Nextmug avoids potential app connectivity issues that many people experience with Ember (more on that below).  The heat lights indicate how warm the drink currently is and whether it's actively heating up, and although it's not as detailed as Ember through the app, having this information on the side of the mug is helpful and more than what you get with Kepwam.

Overall, it's a great balance of functionality, ease-of-use, aesthetics, affordability, and control.

See Nextmug

A Great Alternative
​​Kepwam impressed us with its longer battery life and lighter weight despite having the largest volume, and the larger handle will certainly be appreciated by many people with larger hands.  So if you're looking for a stable workhorse that doesn't break the bank, it's hard to go wrong with Kepwam.

The included slider lid is not fully waterproof, but it's much better than Nextmug (lid has a permanent opening) or Ember (no lid included).

However, we don't think Kepwam is quite as good of a gift option as Nextmug.  The handle is not as comfortable to hold as Nextmug or Ember, and the lighter weight can lead to the perception that it's not as durable or premium.

See Kepwam

Consider Avoiding
To be fair, Ember has a lot of great things going for it.  This was the original smart mug on the market, and they continue pushing boundaries by letting you use the app to see and set the exact temperature of your drink.  The sleek design also looks and feels both fantastic and premium.  And it has the fastest heat-up and recharge rate.

However, Ember has a few significant drawbacks that make it hard to recommend.  The handle is quite small, so people with larger fingers might not find it as comfortable as Nextmug or Kepwam.  It's also the most expensive mug, and that's despite not coming with a lid (you can buy one separately though).

​More significantly, many users (including us with Android) experience disconnect issues and have had to reconnect the mug multiple times.  If you're someone like me who doesn't function well before coffee, having to troubleshoot an app before getting it to work right is...not great.  At least Ember sticks with the last known setting though, so that helps.

Maybe it's worth a try for yourself if you really want that level of control, but our recommendation is to steer clear of Ember, at least until there is noticeable improvement with the app reviews.

See Ember

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Testing

Heat-Up Test
I completely charged each mug, filled them with exactly 13 ounces of tap water, then set them to the highest temperature setting.  And to show you how they compare to a more traditional option, I took this all-ceramic unheated Momnt Mug and put it on a warming plate.

The results showed that the more expensive the mug, the faster it heats up with Ember having the fastest heat rate.  However, Nextmug and Ember also ran out of their charge much faster each lasting just under one hour, while Kepwam was like the tortoise in the race going slow and steady for almost an hour and a half, eventually finishing just a fraction of a degree below Ember.  

Holding Temp Test
​Notably, none of them were able to reach their target temperature when they had to heat up the water from room temperature.  So next, I did temperature maintaining test based on how you'd actually use it by pouring hot water into each mug and seeing how long the battery would last on its hottest setting.

Because the water is already hot, the mugs don't have to spend as much battery heating it up but surprisingly Nextmug had almost the same battery result as before.  Ember's battery life extended to 69 minutes, and that's 13 minutes longer than the previous test.  Kepwam's battery lasted the longest with a battery life of 93 minutes, or about 6 minutes longer than the heat-up test.

Nextmug and Ember both settled a few degrees lower than their advertised high temperature settings, though you could see that slowly drop off as the battery started getting lower before plummeting after running completely out of charge.  Kepwam had a bigger discrepancy between its advertised high temperature of 149 degF, seeming to settle around 143 degF for most of the test.

Recharge Test
​Next was the recharge test.  With each mug's battery depleted, I put them all back on their charging coasters to see how quickly they returned to full charge.  Ember was the fastest, and Nextmug wasn't far behind.  Kepwam took much longer, needing over 4 hours to completely charge.

Scratch Test
Next was the scratch test.  Thankfully each mug comes with a grip pad to prevent scratches on the bottom.  To test the coating on the side, I made 4 light passes on 100 grit sandpaper and noted the results.  Honestly, each one held up pretty well.  There are some obvious scratches because the sandpaper is so coarse, but it didn't cut through enough to show the stainless steel construction underneath the ceramic so it must be a fairly thick layer.  Kepwam's scratches were more noticeable, but that's probably more because the Nextmug and Ember mugs are black so it's just harder to see.

Waterproof Test
First I submerged the electronics with the mugs off for 1 minute, and each one worked fine after.  Then I repeated it with the mugs turned on, and they all did OK again.  The blinking you see here is just the mugs detecting that they're empty so they're starting to automatically turn off.  And just to confirm they're still working, I filled each mug after the 2nd waterproof test and turned them on, and each one began heating up the water.

So based on this test, each mug has acceptable waterproofing.

Customer Service Test
And last in case something does wrong and you end up having to reach out to the company, I also did a customer service test to get a general idea about how responsive each company is.  I sent the same three questions to each one.  Then I noted how quickly they responded, if they fully answered the questions, and if it was an automated response at first, how easy was it to get through to an actual human.

Nextmug and Kepwam both had a human response within one day that fully answered the three questions.

Ember's response was not as good.  First was an immediate AI-powered automated response that answered parts questions but not very well.  For example, I asked for the battery capacity in mAh, but the response just noted their marketed battery life of 80 minutes.  It said my inquiry would be transfered to the Ember team to respond with more detailed specifications, but as of me writing this post it's been this audio it's been 16 days and I have not heard back.