Price - Green case should be fairly affordable for a phone case. Some higher end phone cases can be as much as $60, so we shouldn't go higher than that. Our phone case will have electronics in it, so this may be challenging, but will still be achievable.

Comfort - Green case should be as slim and light as possible without compromising performance. Most people don't want to add much weight to their phones or make them too bulky as then they get hard to hold and carry, so making it slimmer will appeal to more people.

Performance - Green case must output/store enough power to charge the phone efficiently. Being able to generate or store too much power will make Green Case bulkier, so finding a sweet spot between comfort and performance is ideal.

Integration - Charging provided by Green Case should be seamless or near-seamless, and should be optimized to be efficient.

Durability - Green Case should be fairly durable, for example the solar panels not easily breaking, electrical connections not breaking, and providing a fair amount of protection to the phone as well.

Ease of Use - The solar panels must work and work in a way that makes it convenient to use while the phone is being used. They should face up while the phone is being used, without compromising comfort.