Field test

Before making the final design prototype, I decided to take the holder with me on my morning trip to the school. Usually, I am carrying a heavy bag in one hand and using my smartphone in another. Almost ideal situation to check. Here are some notes about the experience:

• As expected, one hand is still free, and I can take selfies.

While carrying, the holder is shaking a bit. Thus, it was correct to pic dimensions close to the cup. Probably, the smaller container will be not so secure in the holder, but folded accordinon can help it.

It became clear that the ring must be easily and freely up and down on the surface. Especially it is seen when you up the hand to hold something, for example.

Bag legs are definitely useless and must be replaced with flat silicon rings.