What are some alternatives?
When comparing Dot Watch and Holo, you can also consider the following products
Moto 360 - The round smart watch is finally here.
Apple ARKit - A framework to create Augmented Reality experiences for iOS
Fitbit Versa Lite - Fitbit's new smart watch starting at $160
AirMeasure - Turn your phone into a ruler with the power of AR
Blocks - Empowering designers to build great websites without writing a line of code. For web and OS X.
Made With ARKit - Hand-picked curation of the coolest stuff made with ARKit