Some products, a priori banal, make the difference through small things. This armlet Axtion Night Run Armband for smartphones small society The Joy Factory is a fine example.
1/Design
The Axtion cuff The Joy Factory is relatively thin, and overall design is sleek. I particularly appreciate its manufacturing quality. The window that reveals the smartphone is obviously tactile. The product is designed to hold a smartphone with dimensions equivalent to those of an iPhone 5. I did the test with it elsewhere. No pun intended, the cuff fits like a glove. A scratch is used to keep everything in the arm. Above all, the difference with the other arm bands, it is the presence of the plastic support around which may partially wrap the cable headphones or earphones connected to the smartphone. A notch at each end allows to thereby lock the cable. Small detail interesting cuff has a flat pocket, discreet, identical surface smartphone compartment: it allows to slide a small object, such as the key to the house or that of his car. 
I did not but it has mentioned cuff reflector elements, so that you distinguish at night. But it really is not this aspect that caught my attention Axtion cuff The Joy Factory.
2/Field
It is the cable reel (with securing slot) that makes the difference. Precisely because it allows to adjust the cable length: it no longer flutters in every sense when short. Very convenient.
Price € 30.
I love
the winding and fixing the cable system. 
The build quality. 
The secondary pocket.