Last week, I had a delivery of a set of Flic buttons. They're simply small, low-energy bluetooth buttons that can be used to control... well... almost anything you like!
The form factor is really nice - they're about the size of a stack of 4 US quarters, come with a sticky back and are covered in nice, soft silicon in a range of colours. You can also additionally add a clip to the back so you can wear the button on clothing or clipped to a bag. The production values on them are really good and they feel like quality buttons. They have a pleasing LED red light inside them that glows through the inset text when they're being configured and the button press feels responsive and "pleasingly pushable", if you know what I mean.
To try them out, I set up a button for my husband. You see, in our bedroom, I control all the lights via a small remote (the Aeon Minimote), however I often fall asleep first and then my husband grumbles that the remote is "all the way" on my side of the bed and he has to fumble with his phone, find the app, turn everything off, blah blah.
So, I gave him the first Flic button to do the same things on his side of the bed - the button is stuck to the side of his night stand. A single press turns off all the lights, a longer press turns the night stand lights on. It took less than a couple of minutes to set up the whole process, including creating the IFTTT channels to talk to SmartThings.
The buttons took seconds to pair with my phone (Android Marshmallow, Nexus 5x) and the app itself is nicely designed with lots of ready-to-use options, plus having IFTTT and a HTTP channel means that if you're into DIY/coding you've got an even wider set of options. The app has some cute details including wobbling the buttons in the app as they're pressed in the real world.
Conclusion
The buttons are nicely made, easy to use and convenient for shortcuts. They take normal coin-cell batteries and should last a good long time. They do however need to be within 50 metres of the paired phone, so if you want to set them up to work when the connected phone is not in range, you're out of luck.
The cost is somewhat prohibitive. They're $34 each! I bought my on pre-order way back in July - getting a set of 3 + clip for $99 + $10 shipping. They're currently selling packs of 4 for the same price ($99 + $10), so given that I pre-ordered and waited 6 months for them, I'm not exactly over the moon that they didn't give me the option to change my order to a pack of 4. If you're looking for buttons to control a z-wave system, the Aeon Minimote is less than $30 and has 4 buttons with multiple modes and doesn't requite a permanent phone connection.
If you don't mind the money and you intend to use them as a companion to your phone's presence, the buttons are sound, nice to use and the software so far is good. I've heard on the grapevine that iOS users are having trouble getting them paired (the Amazon reviews are certainly leaning that way), so you might want to check on that before shelling out, however.