There’s a $40 one sold at Walmart, Ion brand, no app at all, plugs in the wall, not USB.
It worked well… for about a year. The metal contacts on the bottom corroded, and the battery duration dropped. I’m using a four-dollar candle warmer now, it’s the better choice.
I’m tempted to buy one of those battery heated coffee mugs, but they all use an app and seem terrible for the environment.
You can use a plug-in candle warmer to fairly good effect, as long as you start with hot liquid.
There’s a $40 one sold at Walmart, Ion brand, no app at all, plugs in the wall, not USB.
It worked well… for about a year. The metal contacts on the bottom corroded, and the battery duration dropped. I’m using a four-dollar candle warmer now, it’s the better choice.
This one:
https://www.walmart.com/ip/ionMug-Charging-Coaster-12oz-Stainless-Steel-Self-Heating-Coffee-Mug-with-Lid-3-5-x-3-5-x-5/809689677