While there isn't a specific "gadget" or "app" highlighted, the episode focuses on the following crucial investigative elements:
: Polly mentions a specific location she needs to visit, which becomes the primary clue leading the team to a breakthrough in the case. [S3E22] She's Got Us
: Dr. Daniel Charles is brought in to help Lindsay and Halstead connect with Polly, who is disoriented and heavily traumatized. While there isn't a specific "gadget" or "app"