A question anyone in the Smart Home industry will know all too well, "will it work with....".
This question is incredibly vague and open ended question that can either end in disappointment, confusion or even happiness; depending on the situation.
Lets take an example, will my 'Nest' Thermostat work with my Smart Home? Now the response from most people would be something along the lines of 'Nest is it's own product with an App and it can talk to a few systems'. Deep down some more tech savy people will know it has a platform which allows commands to be sent to the Nest system.
The question that will get fired back should be "What are you trying to achieve?". By using one system for heating and tying another for lighting and have everything in one place could prove to be troublesome and the end result is normally not as expected. The ideal situation is to find a solution which has as many features as possible all in one place.
Another example, can I use 'Alexa' to control my Home. Some more off the shelf products will work yes absolutely if you are looking to use voice control for other things like "Set Movie Mode" which will set the lights down, lower blinds, turn on TV & BluRay player, you can do this by sending HTTP commands out to whatever system you like. This will allow almost unlimited number of integration possibilities.
At the end of the day, if you ever think that this question may pop up; you have to ask yourself a few other things:
1. Am I going to expand, can I find a better solution?
2. Will it be easy and/or possible? (if it takes 3 weeks to stitch together, might not be worth it)
3. What am I gaining out of this?
Once these have been answered you will your next steps!