I wonder why they wouldn't work on an extension app for the wearables, especially Apple Watch.
I understand their decision to sell a device, but people who already own a smart wearable probably won't get another one that will only help you with catching Pokemons.
They could have worked on a little more complicated device that could do some tracking and notifying built around the concept of Pokemon - and help you catch them.
Having that said, $35 is not a high price.