Best answer: There are plenty of options from brands like C by GE and Eufy, but LIFX makes the best smart bulbs that don't need a hub. They're pricey, but they work well and play nicely with other smart home gadgets.
Amazon: ($46)
No hubs needed
Philips Hue may be the most recognizable brand in the smart home space, but to many users' frustration, you need a hub to use its bulbs. This adds yet another expense to the already pricey lights, and setup can get complicated since the hub needs to be plugged into your router. Thankfully, not all smart bulbs require a hub.
LIFX makes brighter, more vivid bulbs than Philips Hue for roughly the same price, and they operate over Wi-Fi without needing any additional accessories. You can link them to other smart home gadgets like the Nest Thermostat, and they can be controlled with your voice assistant just like a Philips Hue bulb. LIFX bulbs come in different shapes and sizes to fit various lighting fixtures, and you can even get other form factors like light strips and panels.
You can also get independent bulbs from brands like Eufy, Anker, and C by GE. While each bulb comes with its own set of pros and cons, the important thing is that they can all be controlled through your phone without any kind of hub — though the C by GE bulbs, for example, typically operate over Bluetooth and will still require a hub to use remotely over Wi-Fi.
Even Philips Hue technically makes a smart bulb that doesn't require a hub. The includes a white-only bulb that can be controlled using a dimmer switch; this is a nice basic smart bulb, but you'll still need a hub to control it with your phone.
Wi-Fi bulbs
LIFX A19
The best smart bulbs that work without a hub
LIFX offers a variety of different bulbs that all work over Wi-Fi without a hub and integrate with other services like Google Assistant and Nest. They're some of the brightest smart bulbs around, and display a wide range of colors.