I'm new to this forum, so please refer me to the previous post if this topic has already been covered. I fly lots of Angel Flight trips from California's Central Valley to Palo Alto, and with the weather changing, I'd really like to get this resolved. Yesterday I flew the GPS RWY 31 approach in VMC, with the approach loaded in both my KLN 94 and ForeFlight, and I noted these discrepancies: On the leg from DOCAL to PUDBY, the chart says 329 degrees, the KLN said 330, and ForeFlight said 335. On the leg from PUDBY to RWY31, the chart says 322, the KLN said 323, and ForeFlight said 327. I think part of the difference is that the magnetic variation has not been updated for a while, so the chart is a little off. I'd appreciate an explanation of the differences and how to actually fly the approach.