Fit a range of bottle types: Babies can be fickle, and some go through a period of preferring one bottle shape or size over another. The best bottle warmers accommodate a range of bottle types, models, shapes, sizes, and materials, including short, squat bottles; narrow-neck bottles; and those made from plastic, silicone, or even glass.
Be intuitive to use: Simple-to-set timers and controls, and a clear signal to let you know when the heating cycle is complete, make bottle warmers easier to use. The best ones have an automatic shutoff and/or internal thermostat that prevents bottles from becoming too hot.