We hired ISS to help create authentication tools for our NFC chips. They helped to connect to the chips' auth APIs, build a server that could store exchanged information, then generate auth tokens for different websites to receive during sessions.
ISS met all our expectations, and helped our project become a tangible useful real-world project. They are also very fast in their development cycles, and always delivered on time or faster than expected. The team constantly helped to propose multiple solutions to a problem, and then would execute on it quickly, and stay at it until it was solved or delivered.
I think the most impressive part of working together was that we always looked forward to our interactions, and the process of design and engineering became a fun collaboration. With them it feels like any product idea or goals can become a tangible reality quickly.