When Zoe calls Rachel from the restaurant, her iPhone reads, "Friday, October 19." Moments later when she texts Rachel, the time stamp reads, "Nov 1." It is interesting to note, however, that the times for both events read 2:32 and 2:33, respectively.
When Zoe receives a message from Francis (19m41s into the episode), she holds up her iPhone and the screen image rotates from landscape to portrait, which shows that she does not receive an actual message, but is just looking at a screen shot of a message - the lock screen on an iPhone does not rotate.