Date: 201704
Local time of day: 1801-2400
Location: ORD.Airport, IL
Flight conditions: VMC
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B ORD
ATC / advisory: TRACON C90
Aircraft component: Electronic Flt Bag (EFB)
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Workload; Confusion; Distraction; Situational Awareness
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; Flight Crew Became Reoriented
Contributing factors: Equipment / Tooling
Primary problem: Equipment / Tooling

Narrative: Unexpected JeppFD-Pro App failure on approach. I am writing this report to highlight a particularly concerning failure of the JeppFD-Pro App at around 4000 feet on approach to ORD Runway 9L. Sometime during the downwind leg to ORD 9L; my iPad went into screen saver/sleep mode. Upon 'waking up' the iPad; I selected the JeppFD-Pro app and received the following error message:'iPhone Distribution: Jeppesen Sanderson; Inc. has not been trusted on this iPad. Until this developer has been trusted their enterprise apps will not be available for use.'I then closed the error message; double-clicked the Home button and closed the JeppFD-Pro app. I reselected the app and received the same error message again. At this point; I handed the aircraft over to the First Officer and told him I was going to reset the iPad or get out a chart. We were prepared for the approach and the weather was CAVOK. Believing an iPad restart was just as safe and quick at that point in time as pulling out the charts; I shut down and restarted the iPad. A few seconds later; the iPad was up and running again. I selected the JeppFD-Pro app and once again received the error message. At this point; I took the aircraft back; mentioned my failed JeppFD-Pro app to the First Officer and asked him to pay particular attention to any ATC instructions out of the ordinary as he had a working JeppFD-Pro opened and ready to go. We continued to an uneventful landing and taxied to the gate. After the flight; I proceeded to ORD Flight Operations to attempt to re-download the app. However; once connected to the company network; the JeppFD-Pro app opened normally and all functions worked correctly. Note: my iPad was in Airplane Mode during the flight.A few points to note here. One; I feel we were fortunate that the weather was nearly perfect at an airport I am very familiar with. This could have been a bigger issue in bad weather; at an unfamiliar airport and with any kind of go-around or abnormal situation. Two; this app appeared to fix itself once connected to Wi-Fi in Ops. Following this logic; Wi-Fi in the flight deck may have fixed this immediately. Three; this very situation is one of the unforeseen technology glitches or failures that leave many of us concerned about the future plans to remove all paper charts and paper QRH binders from the airplane.Thank you for looking into this; I welcome any findings you have regarding why this happened and how we can avoid it in the future.




Synopsis: B737 Captain reported the JeppFD-Pro app on his iPad malfunctioned while on approach. The problem was fixed on the ground once the iPad was connected to Wi-Fi.