One of the most common areas that people start out with when they begin implementing a smart home is lighting. It is relatively easy to do, and is a very practical area to automate. Lighting is also probably one of the areas that has the most options from the most vendors. You probably have more lights than anything else in your home to potentially make smart, so it's important to try to make the right decision from the beginning.
Smart Switches vs Smart Bulbs
One of the first questions you will run into is, should I buy smart bulbs or smart light switches? They both have their uses, and they both have their pluses and minuses. Personally, I think it is best to install smart switches/dimmers. My first HomeKit purchase was a Hue Color Bulb Starter Kit and a Lutron Caseta Wireless Dimmer Starter Kit. I installed the Hue kit first because it was the easiest, and I installed my first Caseta dimmer a few days later. I still have the Hue bulbs installed, but I didn't buy anymore after that first purchase. Whereas, I have over 50 Lutron dimmers installed. Here are some of the reasons I prefer smart switches over smart bulbs:
after a few days, the novelty of changing the color of your lightbulbs wears off, and you find very little use for it
using smart bulbs (instead of smart switches/dimmers) causes conflicts with your existing switches - if you turn the light switch off, you lose the ability to control the smart bulb - there are work arounds, but be aware before you make a big purchase
using smart light switches/dimmers (instead of smart bulbs) is usually better, because your house will continue to operate as it always has (great when guests come over), unlike the problem you get when changing the bulbs, but you still gain the ability to use smart lighting features
changing switches can be less expensive than bulbs because they never need replacing and you only have to replace one switch for multi-bulb lighting installations (candelabras, chandeliers, track lighting, can ceiling lighting, etc)
consider using colored bulbs (or light strips) for accent lights only, as opposed to your main lighting
Everybody has different opinions, or maybe you rent so you don't want to replace the switches, but I have found that installing smart switches is a better option than smart bulbs. This page has some tips on how to replace your light switches if you have never done this before.
As I indicated above, after the initial novelty wore off (literally three days after install), I found very little use for colored lightbulbs. Having colored accent lighting can be useful in certain areas, however I find light strips are generally better suited than bulbs for accent lighting, depending on location.
Many people don't necessarily want colored lights, but they do want to adjust the temperature of their white lights. I still don't find this need enough to recommend over smart switches, and you can also purchase bulbs with the white color balance you prefer.
Light Strips are great for accent lighting. Under cabinets is a common area. (Please don't say behind the back of your TV, I would never do that). My home theater has light strips going around the ceiling perimeter of the room, and it looks fantastic. I have them set to a yellowish (popcorn) color at 1% brightness during movies and a little brighter (10%) before and after the movie. Looks just like public theater lighting.
Wall Outlets and Dimmers
Don't forget, you can also plug lights into smart wall outlets and even smart wall outlet dimmers. This can be useful if you want to automate floor lamps and holiday lighting. See the Outlets section for information about smart wall outlets.
What I Use:
Lutron Caseta dimmers all the way. By far the most reliable piece of HomeKit gear out there. 100% rock solid. Easy to install (no neutral wire required). I have them installed in 3-way and 4-way applications. Lutron Caseta wireless devices uses their own proprietary radio signal called RA2, and it is bullet proof. The devices pair to the Lutron Bridge, which helps the switches be more responsive and reduces the number of devices on your home Wi-Fi.
I also have some Eve Light Strips (with extensions) that I use in my home theater for accent lighting. They connect over Wi-Fi, and are very bright when run at 100%. I have them set to a yellowish (popcorn) color at 1% brightness during movies and a little brighter (10%) before and after the movie. Looks just like public theater lighting.